Question # 1

Shear stress addresses to the:

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Volume changes due to the applied stress

Shape changes due to the applied stress

Length changes due to the applied stress

All of the above

In an optical fibre the speed of light is

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Directly proportional to its refractive

Inversely proportional to its refractive inedex

Independent of refractive index

Directly proportional to square of refractive index

The sink in the heat engine is at

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Low temperature

High temperature

Zero temperature

None of these

Under what circumstance would a vector have components that are equal in magnitude ?

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45^o , 145^o , 245^o

135^o , 225^o

45^o , 135^o , 225^o and 315^o

None of these

Least distance of distinct vision

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Decrease with increasing age

Increases with increasing age

Does not vary with age

May increase or decrease with age

Choose an answer

Equation of continuity

Bernoulli's theorem

Toricelli's theorem

None of these

The velocity of efflux is 100 m/sec and area of hole is 0.06 cm²how much volume of water will flow out of hole in one second

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6.0 x 10-⁴m³

6.0m³

600m³

6.0cm³

In Young's double slit experiment,the separation between the slits is made 3 fold the fringe width becomes

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1/3 times

1/9 times

3 times

9 times

Repeaters are the devices which regenerate the signals and are placed at about

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20 km

30 km

40 km

50 km

A Carnot engine takes 300 cal of heat at 500 K and reject 150 cal of heat to the sink. The temperature of sink is

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1000 K

250 K

750 K

125 K

Which of the following statement about centripetal and centrifugal force is correct

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They are oppositely directed

They cancel each other

Both are on the same body

None of these

The ‘emf ’ is always even when no current is drawn through the battery of the cell:

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Zero

Present

Absent

Maximum

When the temperature difference between the source and the the sink increases, the efficiency of the heat engine will

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Increase

Decrease

Is not affected

May increase or decrease depending upon the nature of the working substance

Who proposed wave theory of light

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Huygens

Galileo

Einstein

Newton

When monochromatic light is incident, making certain angle, on a thin parallel film, the interference fringes formed are

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straight

circular

square

plane

How many types of strain is

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1

2

3

4

When the length and area of cross-section both are doubled, then its resistance:

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Will become half

Will remain the same

Will be doubled

Will become four times

After curie temperature iron is

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Ferromgnetic

Diamagnetic

Paramagnetic

None

The fibre core has constant refractive index such as

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1.48

1.5

1.52

1.56

Which of the following material have young and bulk modulus are same

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Brass

Bone

Aluminum

Steel

The expression of scientific notation is

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One non-zero digit left of decimal

One zero digit left of decimal

Two zeros and one non-zero digits left of the decimal

None of these

Which one of the following is an optically active substance?

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Quartz crystal

Calcite crystal

Sugar solution

All of these

The branch of physics which concerned with the ultimate particles of which the universe is composed is known as

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Solid state Physics

Particle Physics

Nuclear Physics

Atomic physics

When the velocity of a body is doubled

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Its K.E is doubled

Its P.E doubled

Its momentum is doubled

Its acceleration is doubled

Propagation of light in an optical fiber requires that light should be

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Refracted from air to fiber

Continuously refraction

Totally reflected within the fiber

Both B and C

The product of pressure P and volume V of an ideal gas is

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Constant

Approximately equal to the universal gas constant

Directly proportional to its temperature

Inversely proportional to its temperature

The medium in which speed of light is the same in all directions is called:

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Homogeneous

Heterogeneous

Non-homogeneous

Free space

Negative and positive charge in a hollow sphere are equal in the number then flux from the surface will be

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Zero

Positive

Negative

Flux will be both negative and positive

The nonrenewable energy source is

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Sunlight

Hydroelectric

Uranium

None of these

Which of the following is not a perfectly inelastic collision?

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Striking of two glass balls

A bullet striking a bag of sand

An electron captured by a proton

A man jumping onto a moving cart

The efficiency of a practical heat engine:

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Can be 100%

Can not be 100%

Is always Zero

None of these

Joule-second is the unit of:

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Energy

Heat

Planck’s constant

None of these

Measurement of a standard metre in terms of the wavelength of red cadmium light is

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1,563,163.5

1,553,363.5

155,553.5

1,553,163.5

A diesel engine converts heat energy into work by

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35%

40%

35% to 40%

45%

When the length of a microscope tube increases its magnifying power

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Decreases

Increases

Does not change

May increase or decrease depending on the observer and the place of observation

The maximum kinetic energy of emitted photoelectrons depends upon:

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The intensity of incident light

Frequency of incident light

Metal surface

Both frequency of incident light and metal surface

The precision of measurement in physics depends

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Average values

Least count of instrument

Error free instrument

b and c

A perpetual motion is that motion which is

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Temporary

Continuous

Forever

None of these

A charge -4 μ C is at origin and +16 μ C is at a distance 3 m on positive x-axis the zero field is located at

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3 m along y=axis

3 m along negative x-axis

3 m along positive x-axis

6 m along negative x-axis

A motor runs at 20 rev/s and supplies a torque of 75Nm. Power delivered by it is

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6.12 hp

12.6 hp

7.3 hp

8.3 hp

The resistance of operational amplifier between inverting and non-inverting terminal is of the order of:

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Few Ohms

Mega Ohms

Few Kilo Ohms

Micro Ohms

The position of a new wavefront after a certain interval of time can be found by constructing a surface that is

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A tangent

A tangent envelope

Curved surface

None of these

Polaristion is a phenomenon associated with a certain type of wave.

Which condition must be fulfilled if the wave is to be polarised?

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It must be a longitudinal wave

It must be a light wave

It must be a transverse wave

If yellow light emitted by sodium lamp in Young's double slit experiment is replaced by blue light of the same intensity:

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Fringe width will decrease

Fringe width will increase

Fringe width will remain unchanged

Fringe will become less intense

Identify the correct unit of pressure among t bese

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kgms^-1

kgm^-1s^-2

kgm²s^-2

kgm^-2s^-1

Angular momentum of a particle is

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Parallel to its linear momentum

Perpendicular to its linear momentum

Inclined to its linear momentum

A scalar quantity

Two forces P and Q have a resultant Perpendicular to P.the angle between the forces is:

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tan^-1 (-P/Q)

tan^-1(P/Q)

sin^-1(P/Q)

cos^-1 (-P/Q)

A cell of negligible resistance and e.m.f 2 V is connected across a series combination of 2,3 and 5 ohms. The p.d. across the 3 Ω resistor is

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0.6 V

1/3 V

2/3 V

4/3 V

The example of nuclear fusion is:

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Formation of barium and krypton from uranium

Formation of plutonium -235 from uranium -235

Formation of helium from hydrogen

Formation of water from hydrogen and oxygen

Which of the following phenomenon is not application of Bernoulli s equation

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Swing in cricket ball

Flying of airplane

Working of carbonator

Beats

A ballistic missile moves under the result of the superposition of

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one independent motion

two independent motions

one dependent motion

two dependent motions

Substances which flow easily are

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Water

Kerosene oil

Petrol

All of these

A frame of reference stationed on Earth in approximately an example of

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Inertial frame

Non-inertial frame

Every frame

None of these

The velocity of a projectile is maximum

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at the point of projection

just before striking the ground

none of them

both of them

A point charge Q is placed at the mid-point of a line joining two charges,4q and q. if the net force on charge q is zero,then Q must be equal to

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-q

+q

-2q

+4q

Optical fibres function on the principle of

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reflection

refraction

total internal reflection

total internal refraction

The characteristics of steady flow is

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Non-viscous

Incompressible

Streamline

All of these

One Pascal in SI is equal to

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One newton metre

One newton metre^-1

One newton metre^-2

One dyne cm²

A rain drop of radius r falls from a certain height h above the ground. The work done by the gravitational force is proportional to

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r

r²

r³

r⁴

The ideal gas obey gas law at:

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Low tempratures and high pressures

High temperatures and low pressures

All temperatures and pressures

None of these

Approximate power of Jumbo. Let Aircraft in watts.

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1.2 × 10⁶

1.3 × 10⁸

1.2 × 10⁸

1.1 × 10⁹

By dimensional analysis, we can find

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Correctness of formula

Derivation of formula

Physical nature

All of these

The unit of power of a lens is

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Meter

Watt

Horsepower

Dioptre

In projectile motion the vertical acceleration is

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Zero

Maximum

'g'

None of these

The minimum number of lenses used in compound microscope is

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1

2

3

4

The isothermal and adiabatic processes are employed in order

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Two isotherm and then two adiabates

Only isothermal one adibate

Only isothermal process

Only adiabatic process

The SI units of flow rate are

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m²s^-1

m³s^-2

m³s^-1

m²s^-2

In slow Compression of a gas in a cylinder is reversible as the compression can be changed to expansion by

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Rapid decreasing the pressure

Slowly decreasing the pressure

Extremely decreasing the pressure

None of these

The terminal velocity of for a water droplet of radius 10^-5 m is of the order of

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1 cm/s

1 mm/s

1 nm/s

1 μm/s

The word fluid means

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To rise

To fall

To flow

To oppose

The frequency of the fundamental mode of open at one organ pipe is 400 Hz. Ifone end of pipe is closed the fundamental frequency will be

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800 Hz

600 Hz

400 Hz

200 Hz

The advantage/advantages of fiber optics than radio wave carriers

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Much wider band width

Capability

Immunity

All of these

Due to Plano convex lens and the plane glass plate the thickness of air film changes from the center to outward

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Increasing gradually

Decreasing gradually

It is constant at the centre

None of these

When an atom is surrounded by large number of atoms their the energy levels are

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Distinct

Very close

Energy band

None of these

A _____ lens is used in the apparatus to get newton's ring:

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Plano-concave

Plano-convex

Convexo concave

Double covex

Source of light used in the fibre optic communication

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Led

Laser

Photo diode

Both a and b

Which one of the following is the example of reversible reaction

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Melting of ice

Work done against friction

Heat produced by current

Conduction of heat from hot to cold body

In cause of YDS experiment, the distance between adjacent bright fringes is given by

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Δy =λL/d

ΔY = L/λd

ΔY =λ/L

None of these

Which one of the following is nearly monochromatic

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Light from candle

Light from simple lamp

Light from sodium lamp

Light from sun

In which of the optical fibres, the propagation of light signal is through continuous refraction?

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multi-mode step index fibre

multi-mode graded index fibre

both of them

none of them

A steel wire 12 mm in diameter is fastened to a log and them pulled by a tractor. The length of stire between the log and tractor is 11 m. The force of 10,000 N is required to pull the log. What is stress

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84.46 MPa

85.46 MPa

88.46 MPa

89.46 MPa

The decrease in velocity per unit time is called

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deceleration

acceleration

uniform acceleration

variable acceleration

If a car at rest accelerates uniformly to a speed of 144 km/h in 20 s it covers a distance of

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20 m

400 m

1440 m

2880 m

Using a graded index fibres the time difference is reduced to about

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0.5 ns per km

1.0 ns per km

2.0 ns per km

2.3 ns per km

In blood red cell concentration is ______%.

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25

35

40

50

Velocity time graph can never be perpendicular to time axis,it implies

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Zero acceleration

Zero velocity

Infinite acceleration

Zero displacement

the ratio of mean K.E of chlorine and oxygen molecules at same temperature is

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16 35.5

35.5 16

(35.2)²16

1 1

The moon produce tidal effect in the sea by pulling

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The land

The sea

Both

None of these

The magnetic field due to the electric current in a conducting wire is:

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Towards the centre of the conducting wire

Circular around the conducting wire

In the direction of the electric current

In the direction opposite to the electric current

Experimental demonstration of wave nature of light was given in 1801 by

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New ton

Maxwell

Thomas young

Huygen

How many phone calls can be carried by single mode step index fibre

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25000

96000

14000

21000

A car is moving high velocity when it takes a turn.A force acts on it outwardly because of

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Centripetal force

Centrifugal force

Gravitational force

All of these

The capacitance of a parallel plate capacitor does not depend upon

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Area of plates

Medium between plates

Distance between plates

Metal of the plates

Polymeric solids have the properties like

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No definite shape

No definite structure

Partially crystalline solids

All of them

The travel time of light from Moon to Earth is

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2 min 10 sec

1 min

1 min 20 sec

3 min 30 sec

Which of the given pair have same dimension

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Stress, pressure

Elastic modules, pressure

Stress, elastic modules

All have same dimension

Newton's laws are adequate for speeds that are

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low compared with the speed of light

equal to the speed of light

greater than the speed of light

all of them

When the left is moving upwards with an acceleration 'a' then

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T - W = ma

W - T = ma

T = W

None of these

The relation between Cp and Cv is given by

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Cp = Cv

Cp < Cv

Cp > Cv

None of these

For the same value of resistors the output of non-inverting amplifier compared to the output of inverting amplifier is, (ignoring phase difference)

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Greater

Equal

Smaller

Undefined

A system may be in equilibrium when

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the resultant force acting on it is zero

the resultant torque on it is zero

the sum of clockwise and anticlockwise moments (taken about the same point) are equal

all of them

The moment of linear momentum of a body is called

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Angular momentum

Couple

Impulse

Torque

If the vector sum of all the external forces acting on a body is zero, then the body will be in

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rotational equilibrium

translational

complete equilibrium

all of them

If light of low wavelength is used in Young's double slit experiment then width of the fine will

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Decreases

Increase

Not fixed

No change

If drag force is given by F = krv what could be the SI units of k

Choose an answer

kgm²s^-1

kgm^-2s^-2

kgm^-1s^-1

kgms^-1

In Michelsion's interferometer, if 'm' number of fringes are passed in front of a reference point when the moveable mirror is moved a distance L, then

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L = mλ

L = 2mλ

L = mλ/2

L = 3/2 mλ

If a point source of light is placed at the focus of a convex lens the rays coming out of the lens will constitute

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Plane wave fronts

Cylindrical wave fronts

Spherical wave fronts

All of above

Crystalline solids have the properties such as

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Regular arrangement

Covalent bonding

Some what defective

All of them

When two lights waves travelling in the same direction are in phase at any point, they producing

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constructive interference

destructive interference

dispersion

polarization

Fringe spacing ΔY is the distance between two adjacent bring fringes on the screen is

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ΔY = Lλ/d

ΔY = Ld/λ

ΔY = dλ/L

ΔY = Lλ/d m

For which position will be maximum blood pressure in a body have the smallest value

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Standing upright

Sitting relaxed

Lying horizontally

Standing on one's head

Which characteristics of wave, established the Huygen's wave theory in 1801?

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polarization

interference

propagation

all of them

The work done in placing a charge of 8 x 10^-18C on a condenser of capacity 100 μ F is

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32 x 10^-32 j

16 x 10^-32j

3.1 x 10^-26j

4 x 10^-10j

A force passing through the center of gravity of a body

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Results only in rotational motion

Results only in translational motion

Holds the body in equilibrium

None

Young's modulus for tungsten is

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90

190

390

590

For average velocity of a body, it has

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Straight path

Curved path

Steady motion or variable

All of them

The relativistic mechanics in which object move

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Less than C

Greater than C

Equal to C

Approach to C

The horizontal component of a projectile moving with initial velocity of 500 ms^-1at an angle 60° to x-axis is

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500 ms^-1

1000 ms^-1

250 ms^-1

zero

Zirconia is classified as:

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Ceramic solid

Ionic compound

Metal

Either A or B

Either B or C

Who gave the corpuscular nature of light

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Einstein

Newton

Maxwell

Thomas young

Internal friction of fluid is

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Resistance

Viscosity

Cohesive force

Surface tension

Acceleration produced in a body by a force varies

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inversely as the applied force

directly as the mass of the object

directly as the mass of the body

none of them

When the second condition of equilibrium is satisfied, the body has

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no linear acceleration

no angular acceleration

F_x= 0

none of them

An ideal heat engine can only be 100% efficient if its exhaust temperature is equal to

Choose an answer

0°C

0k

100°C

Temperature of source

Linear momentum is a vector quantity and has direction of

Choose an answer

Its displacement

Velocity

Acceleration

None of these

A hole is made in the bottom of a container having water field up to a height h, the velocity of water flowing out of the hole is depend on

Choose an answer

Independent of h

Proportional of h^1/2

Proportional to h

Proportional to h²

The SI units of impulse are

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Nm

Nm²

Nm^-1

Ns

Which of the following have the same unit:

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Stress

Strain

Modulus elasticty

Both (A) and (C)

Both (A) and (B)

The light produced by a laser is all the following except

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Incoherent

Monochromatic

In the form of a narrow beam

Electromagnetic

Adjacent layers in laminar flow are

Choose an answer

Min with each other

Smoothly slide one over the other

oppose each other

None

A gas which strictly obeys the gas laws under all conditions of temperatures and pressure is called:

Choose an answer

Ideal gas

Inert gas

Real gas

None of these

How many electrons are in one Coulomb ?

Choose an answer

6.2 × 10^-23

6.2 × 10^-21

1.6 × 10^-19

Zero

The systolic blood pressure comes when

Choose an answer

Vessel collapse

Cutting off the blood flow

None of these

All of these

Which of the following converts electrical signals into light signals?

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optical fibre

receiver

reflector

transmitter

The rectangular components of force 5 dyne are

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3 and 4 dyne

2.5 and 25 dyne

1 and 2 dyne

2 and 3 dyne

Physical quantities are often divided into ________ categories

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3

2

9

5

Choose an answer

1 PV

2 PV

1/2 PV

Zero

The power of a pump motor is 2 kilowatt.The water raised by the pump per minute to a height of 10 m is nearly

Choose an answer

500 kg

7000 kg

1200 kg

Zero

A body is subjected to a force such that its velocity is doubled then

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Its acceleration is also doubled

Its momentum is also doubled

Its potential energy is also doubled

Its kinetic energy is also doubled

What is the unit of the Young's modulus?

Choose an answer

N m^-2

N m^-1

N m

N m²

Two forces are acting together on an object.The magnitude of their resultant is minimum when the angle between the force is:

Choose an answer

0°

60°

120°

180°

With a step-index fibre, the overall time difference between all the wavelengths arrived at the other end may be about

Choose an answer

43 s per km

33 s per km

1 ns per km

33 ns per km

In YDS experiment, the condition for constructive interference of two coherent waves is that the path difference should be

Choose an answer

Integral multiple ofλ/2

Integral multiple ofλ

Even integral multiple ofλ/2

Both A and C

The SI unit of stress is some as that of:

Choose an answer

Pressure

Momentum

Impulse

Change momentum

Force

Photo cells are used for :

Choose an answer

Security and counting system

Automatic door system

Automatic street lighting

All of these

The high blood pressure is known as

Choose an answer

Diastolic

Systolic

High blood pressure

None of these

Uniform acceleration is defined as

Choose an answer

Average acceleration

Instantaneous acceleration

Equal change in velocity and time

None of these

A beam of light enters air from water.Which of the following characteristics of light will not change in water

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Frequency

Wavelength

Velocity

Amplitude

The weight of 100 kg man in an elevator going up with an acceleration of 4ms^-2will be

Choose an answer

908 N

490 N

100 N

1380 N

The structure of the polymeric solid is:

Choose an answer

An ordered structure

A disordered structure

Intermediate between order or disorder

Any of these

None of these

The capacity of television channels INTELSAT VI satellite is

Choose an answer

2

3

10

20

A women of 50 kg distributes her wright equally over high-heeld shoes. Each heel has an area of 0.75 cm². The pressure exerted by each heel will be

Choose an answer

6.66 x 10⁶ Pa

3.33 x 10⁶ Pa

1.67 x 10⁶ Pa

3.33 x 10^-6 Pa

A line whose tangent at each point is in the direction of an electric intensity at that point is called

Choose an answer

Charge

Voltage

Electric force

None of these

Single mode step index fibre is used to send

Choose an answer

white light

green light

a strong monochromatic light

yellow light

The angle of incidence at which angle of refraction becomes 90⁰ is called

Choose an answer

Incident angle

Angle of refraction

Critical angle

Phase angle

When a horse pulls a cart.the force that makes the horse run forward is the force exerted by

Choose an answer

The horse on the ground

The horse on the cart

The ground on the horse

The ground on the cart

In an astronomical telescope is the objective has the focal length f_o is

Choose an answer

Small

Very small

Long

None of these

The efficiency of a particle heat engine:

Choose an answer

can be 100%

Cannot be 100%

Is always zero

None of these

The original source of Wind energy is

Choose an answer

Tides

Waves

Sun

Moon

For a moving body. at any instant of time

Choose an answer

If the body is not moving the acceleration is necessarily zero

If the body is slowing.the retardation is negative

If the body is slowing.the distance is negative

If displacement.velocity and acceleration at that instant are known,we can find the displacement at any given time in future.

In the hysteresis loop, when the current is reduced to zero, the material

Choose an answer

does not retain magnetism

retains not retain magnetism

retains strong magnetism

none of them

In projectile motion the vertical acceleration is

Choose an answer

Zero

Maximum

'g'

None of these

When the second condition of equilibrium is satisfied, the body will be in

Choose an answer

complete equilibrium

translational equilibrium

rotational equilibrium

all of them

The equations for uniformly accelerated motion can also be applied to free fall motion of the objects by putting

Choose an answer

V_f= 0

Simple 'a'

a by g

None of these

Light appears to travel in straight line because

Choose an answer

It is not absorbed by the atmosphere

It is refracted by the atmosphere

Its wavelength is very small

Its velocity is very large

Solar energy at normal incidence outsides the Earth atmosphere is about

Choose an answer

1.043 Wm^-2

1.2 Wm^-2

1.4 Wm^-2

1.67 Wm^-2

Iron, cobalt and nickle are examples of

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diamagnetic substances

ferromagnetic substances

paramagnetic substances

all of them

The internal energy is similar to the

Choose an answer

Gravitational potential energy

Kinetic energy

Mechanical energy

None of these

The viscosity of water is

Choose an answer

0.019 x 10^-3 Nsm^-2

0.801 x 10^-3 N-sm^-2

6.29 x 10^-3 N-sm^-2

0.081 x 10³ N-sm^-2

Mathematically the vertical velocity component is

Choose an answer

The image of the tip of a needle is never sharp because of

Choose an answer

Polarization of light

Interference of light

Diffraction of light

Reflection of light

The substances in which atoms cooperate with each other in such a way so as to exhibit a strong magnetic effect, are called

Choose an answer

diamagnetic substances

ferromagnetic substances

paramagnetic substances

all of them

Center of mass is a point

Choose an answer

Which is geometric centre of a body

From which distance of particles

Where the whole mass of the body is supposed to be centered

Which is the origin of reference frame

The numerical ratio of velocity to speed is

Choose an answer

Less than 1

Less than zero

Greater than 1

Either less than or equal to one

Nicrom wire is an example of

Choose an answer

Non ohmic device

Ohmic device

Neutral device

Charged device

In a hydroelectric power station, the height of the dam is 10 m. How many kg of water must fall per second on the blades of a turbine in order to generate 1 MW of electrical power ? Take g = 10 ms^-2

Choose an answer

10³ kgs^-1

10⁴ kgs^-1

10⁵ kgs^-1

10⁶ kgs^-1

Two wires of same material have lengths L and 2L and cross-sectional area 4A and A respectively. the ratio of their specific resistance would be:

Choose an answer

1: 1

1: 8

8: 1

1: 2

Acceleration means the speed of the body is

Choose an answer

Increasing

Decreasing

Just stop

None of these

Insulators are those materials in which valence band is

Choose an answer

Empty

Partially filled

Full

None of these

If f = 5 cm and d = 25 cm then the magnification will be

Choose an answer

2

4

5

6

A typical collector which absorbs energy directly from solar radiation upto about

Choose an answer

40 ^oC

70 ^oC

80 ^oC

90 ^oC

A gravity free system, in which satellite moves due to

Choose an answer

The free fall acceleration

Radial accelerations

Gravitational acceleration

All of these

Petrol engine converts heat energy to work roughly

Choose an answer

20%

25%

30%

40%

When a silicon crystal is doped with a trivalent element, then the atom of the trivalent element is known as

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acceptor

donor

either of them

none of them

A medium of dielectric constant 'K' is introduced between the plates of parallel plate condenser,As a result its capacitance

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Increase k time

Decrease k times

Decreases 1/k times

Remains unchanged

Keeping in view the Earth surface the value of g on the equator is

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Zero

Minimum

Maximum

None of these

A man pushes a wall but falls to displace it.He does:

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Negative work

Maximum positive work

Positive work but not maximum

No work

When there are number of forces acting on a body and the body is

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At rest

Motion

Rest or moving with uniform velocity

None of these

A material with high retentively and large corcivety most useful to make

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Electromagnet

Permanent magnet

Choke

None of these

If one of the rectangular components of a vector is not zero, can its magnitude be zero

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It is zero

It if not zero

It may be negative

None of these

Which of the following spectrum have all the frequencies from high to low frequency range?

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Band spectrum

Continuous spectrum

Line spectrum

Discontinuous spectrum

X-ray crystallography can be used to get what information about the structure of a compound?

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the bond angles in a molecules

the number of molecules per unit cell

a picture of the electron density in a unit

all of them

When resistances are connected in Parallel, the effective resistance will be

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Product of the reciprocals of the individual resistances

Product of the individual resistances

Sum of the reciprocals of the individual resistances

Sum of the individual resistances

The more general form of second law of motion is

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F = ma

F x t = mV_f- mV_i

Both

None of these

In equation of continuity, if the fluid is incompressible and the flow is steady, the mass of the fluid is

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Some what conserved

Conserved

Not conserved

None of these

Newton published laws of motion in his famous book "principia" in

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1867

1667

1676

1687

Bouncing off the squash ball several times from wall bears

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Total displacement

Average displacement

No displacement

None of these

The approximate efficiency of solid state laser is

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35%

30%

27%

23%

In thin film colours are due to

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Reflection

Interference

Diffraction

Refraction

For which position will be maximum blood pressure in a body have the smallest value

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Standing upright

Sitting relaxed

Lying horizontally

Standing on one's head

Which of the following quantities is a vector

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Volume

Temperature

Displacement

Density