Question # 1

The ratio of output work per cycle to input energy per cycle is called:

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Entropy

Internal energy

Efficiency

None of these

Bending of light around sharp edges is known as

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Interference

Diffraction

Reflection

Dispersion

The fibre core has constant refractive index such as

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1.48

1.5

1.52

1.56

The path difference and phase difference are related to each other as

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Phase difference = (2π) x path difference

Phase difference = (2π/λ) x path difference

Phase difference = (λ/2) x path difference

Phase difference = (2λ/π) x path difference

The relative permitivity ∈_r for distilled water is

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2.9

1.0008

2.0

2.1

Bernoulli's equation is based upon law of conservation of

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Mass

Momentum

Energy

None

A single converging lens placed close to the eye to see magnified image is called

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A telescope

Compound microscope

Simple microscope

None of these

Electric current is defined as:

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Flow of charges through conductor

Rate of flow of charges through conductor

Flow of electrons

Flow of protons

Most motorbikes have ____________ cylinder/s engine but cars usually have _________ cylinders on the same crankshaft.

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Four , Six

One , four

two , five

None of these

Bulk modulus for bass is

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20

41

61

81

A copper ball of radius r is moving with a uniform velocity v in the oil. The dragging force acting on the ball is F. The dragging force on the copper ball of radius 2r moving with uniform velocity 2v in the oil is

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F

2F

4F

8F

Dimensions of impulse are similar to the dimensions of

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torque

work

force

momentum

A chocolate cookie is a circular disk of diameter 8.5 ± 0.02 cm and thicknes 0.050 ± 0.005 cm the average volume in cm³ is

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2.83 ± 0.3

2.38 ± 0.27

11.35 ± 1.2

9.31 ± 1.12

Wavelength of the wave is the distance between the particles of the medium having adifference of:

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Zero

n

2n

𝜋2

At high speed and for long trajectories the air friction is

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Negligible

Not negligible

More than gravity

None of these

Under same environment the measurement of a physical quantity gives different values. The error in measurement is called

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Random error

Systematic error

Physical error

Uncertainty

No work is done by the body when angle between force and displacement is

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0^o

45^o

90^o

60^o

Stoke's law holds for bodies of the shape

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Spherical

Rectangular

Oblog

All of these

The internal energy of a gram mole of an ideal gas depends upon

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Pressure alone

Volume alone

Temperature alone

Both pressure and temperature

The uniformly accelerated equations are useful only for

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Angular motion

Curved motion

Linear motion

None of these

In Young's double slit experiment, the widths of dark and bright fringes are

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different

equal

zero

variable

If λ = 589 nm d=1.0 mm L=225 cm then fringe spacing ΔY is given by

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1.76 mm

1.80 mm

1.37 mm

1.33 mm

A line which represents the direction of travel of a wave is known as:

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Spherical wavefront

Locus

Ray

Either B or C

For fast moving particles, such as atomic particles in an accelerator, the following branch of physics is applicable

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newtonian mechanics

classical mechanics

relativistic mechanics

all of them

The centre of gravity of an object is

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The force of gravity on the object

The point about which the object rotates

The point at which the total weight of the object act

none of these

Fahrenheit and centigrade (Celsius) thermometers have the same reading at

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-100°C

60°C

40°C

-40°C

If the distance between two masses is doubled, the gravitational attraction between them

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Is doubled

Becomes four times

Is reduced to half

Is reduced to a quarter

In Newton's rings the thickness of air film at the point of contact is

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maximum

minimum

equal to wavelength

zero

The motion of a projectile is

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one dimension

two dimensions

three dimensions

four dimensions

A man sitting in a bus traveling in a direction from west to east with a speed of 40 km/h observes that the rain-drops are falling vertically down.To the another man standing on ground the rain will appear

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To fall vertically down

To fall at an angle going from west east

To fall at an angle going from east to west

The information given is insufficient to decide the direction of rain

A plane wavefront is that which has source

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Nearest

Distant

Near

None of these

The relative velocity before and after the collision is

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V₁+ V₂= V'₂+ V'₂

V₁- V₂= V'₂- V'₁

V₁- V₂=-( V'₂- V'₁)

None of these

The weight of 10 kg body falling freely is

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zero

98 N

9.8 N

10 N

When m₁>> m₂and V₂= 0, the result of their velocities are

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Find the range of the projectile, having speed 30 ms^-1in a direction 30^o above the horizon

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50 m

80 m

90 m

100 m

Elastic deformation of a material is the deformation which is

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Permanent

Temporary

Some what permanent

None of these

The wavelength of X-rays is about

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10^-14m

10^-10m

10^-6m

10^-4m

Hails fall faster than rain drops due to their

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Greater size

Greater mass

Greater area

None of these

The polymeric solids have specific gravity compared with even the lightest of metals

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Low

Very Low

Slightly low

None of these

Phenomenon of interference and diffraction support the:

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Quantum nature of light

Tranverse nature of light

Wave nature of light

Complex nature of light

For interference to occur, the light coming from the two slits should

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be monochromatic

come from the same source

have a constant path difference

all of them

The law of conservation of energy is the base of

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Stoke's theorem

Carnot's theorem

Bernoulli's theorem

None of these

On a diffraction grating which thing acts as a slit

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the lines which are ruled on it

the spacing between the lines

either of them

none of them

Multiplication of a vector is carried out by a

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Number

Direction

Number and direction

None of these

The orbital radius as the revolving body is revolving is

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Very Smaller

Larger

Smaller

None of these

The direction of the linear momentum is the direction of

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speed

velocity

weight

none of them

In case when there is no total displacement and average velocity, then the motion is described by

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Variable velocity

Instantaneous velocity

Initial velocity

None of these

Amorphous solids are called

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Polymeric

Crystal

Glassy solids

All

For geosynchronous satellite the orbital time period is

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Greater than earth s spinning time period

Less than earth s spinning time period

Equal to the earth s spinning time period

None of the earth

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

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Ideal gas

Inert gas

Real gas

None of these

A person holds a bucket of weight 60 N He walks 7 m along the horizontal then climbs up a vertical distance of 5m. The work done by the man is

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300 j

720 j

420 j

None

If solid sphere and solid cylinder of same mass and density rotate about their own axis,the moment of inertia will be greater for

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Solid sphere

Solid cylinder

Both

Equal both

Viscosity of air at 30^oC in Nsm^-2

Choose an answer

0.015 × 10^-3

0.019 × 10^-3

0.151 × 10^-3

0.0179 × 10^-3

The weight of man is an elevator descending down with an acceleration of 9.8 ms^-2will become

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Half

Double

Unchanged

Zero

Light has:

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Wave nature

Particle nature

Dual nature

None of them

Confining the light vibrations in one plane is called:

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Reflection of light

Interference of light

Polarization of light

Diffraction of light

Equal charges are given to two spheres of different radii,The potential will

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Be more on the smaller sphere

Be more on the bigger sphere

Be equal on both the sphere

Depend on the nature of the material of the sphere

If a body is at rest, then it is said to be in

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torque

equilibrium

dynamic equilibrium

static equilibrium

The identity of an element is determined by:

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the number of its protons

the number of its electrons

the number of its neutrons

its atomic mass

The dimensions of ½at²are of

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length

Velocity

Acceleration

TIme

The ratio of electro static force to the gravitational force between them is of the order of

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10³⁶

10³⁸

10⁴⁰

10⁴²

The velocity of a particle at an instant is 10 m/s and after 5s the velocity of the particle is 20 m/s.The velocity 3s before in m/s is:

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8

4

6

7

A beam of light of wavelength is incident normally on a grating of element d the angle between the zero-order and first -order spectra depends on

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λ only

d only

λ and d

λ d and distance of screen from the grating

The magnification is negative for

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Real image

Virtual image

Sometimes for real sometimes for real

Only for cancave lens

The approximate efficiency of fossil fuel power plants is

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20 - 27%

30 - 40%

40 - 50 %

40 - 42%

To increase the magnification of a telescope

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The objective lens should be of large focal length and eyepiece should be of short focal length

The objective and eyepiece both should be of large focal lengths

Both the objective and eyepiece should be of smaller lengths

The objective should be small focal length and eyepiece should be of large focal length

Inspite vibrations the force which hold the atoms in their ordered form is

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Vander vall force

Cohesive force

Adhesive force

None of these

The activity of a radioactive sample is 1.6 curie and half-life is 2.5 days. Its activity after 10 days will be:

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0.8 Curie

0.1Curie

0.4 Curie

0.16 Curie

The term Brownian movement refers to

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Irregular motions of small particles suspended in a fluid

Convection currents in a liquid or gas

Convection currents in a gas but not in a liquid

The stretching of a body beyond its elastic limit

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

De-Broglie received the Nobel prize on his work on:

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Wave nature of particle

Corpuscular nature of wave

Dual nature of particle

All of them

Impulse is the force applied for a very short interval time in which force is

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Constant

Not constant

May be constant for some time

None of these

The concentration in solution can be determined by the property known as

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Solubility

Insolubility

Optical activity

None of these

The fundamental unit which has same power in the dimensional formula of surface tension and viscosity is:

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Mass

Length

Time

None

No practical heat engine can be pergectly

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Ideal

Reversible

Irreversible

None of these

Television signal are converted into light signals by

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Decoder

Transistor

Photodiode

Optical fibre

Two forces of 10N and 15N are acting simultaneously on an object in the same direction Their resultant is.

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Zero

5N

25N

150 N

Thermal and mechanical equilibrium is maintained all the time so that each process is

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Reversible

Perfectly reversible

Irreversible

None of these

If the earth were to stop rotating, the value of 'g', the acceleration during to gravity at Delhi

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Increases

Decreases

Remains unchanged

Becomes zero

A gale blows over a house. The force due to the gale on the roof is

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In the downward direction

In the horizontal direction

In the upward direction

Zero

One light year = ______.

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9.5 x 10^-15m

9.5 x 10¹⁵m

9.5 x 10^-12m

9.5 x 10¹²m

The deformation measured in terms of some twisting angle due to action of stress is known as

Choose an answer

Stress

Linear stress

Compressive stress

Shear stress

Earth receivers huge amount of energy directly from

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Water

Moon

Sun

None of these

In carnot cycle, there are isotherms as

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One

Two

Three

Four

What will be efficiency of carnot engine when it is operated between the temperatures 47^oC and 127 ^oC:

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Reversible

Irreversible

Sometimes A and B

None of these

When the opposite faces of a rigid cube are subjected to shear stress, the shear strain produced is given by

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γ = Δa/a

tan θ

γ = θ

All of them

If the red light is replaced by blue light illuminating the object in a microscope the resolving power of the microscope

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Decreases

Increases

Gets halved

Remains unchanged

In SI system the correct unit of Planck's constant is

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Kelvin

Js

Lux

Candela

In case of destructive interference of two waves, the amplitude of the resultant wave will be ______ either of the waves

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Greater then

Smaller then

Equal to

None of these

A railway engine (mass 104 kg) is moving with a speed of 73 km/h.The force which should be applied to bring it to rest over a distance of 20 m is

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3,600 N

7,200 N

10,000 N

100,000 N

The Permitivity ε_o of free space has the value in S.I. units is

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8.85 × 10^-10 C² N^-1 m^-2

8.85 × 10^-11 C² N^-1 m^-2

8.85 × 10^-12 C² N^-1 m^-2

8.85 × 10^-13 C² N^-1 m^-2

Find the angle between two forces of equal magnitude of their resultant is also equal to the magnitude of either of these forces

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60^o

120^o

180^o

360^o

Consider telecommunication through optical fibers.Which of the following statements is not true?

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Optical fibers may have homogeneous core with a suitable cladding

Optical fibers can be of graded refractive index

Optical fibers are subject to electromagnetic interference from outside

Optical fibers have extremely low transmission loss

Distance to nearest galaxy from earth is

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10¹⁰m

10¹⁵m

10⁴⁰m

10³⁰m

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 monochromatic source of light gives light of

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one colour

two colours

four colours

seven colours

The ballistic missiles are useful for

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Short ranges

Long ranges

Medium ranges

None of these

The SI unit of power is

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Joule

Watt

Pound

None of these

In order to observe interference , the interfering beams must be

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monochromatic

coherent

either of them

both of them

Resistance of 60 watt bulbs in 120V line is:

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20 ohms

240 ohms

0.15 ohms

180 ohms

A light wave produced by oscillating charge consists of a periodic variation of

Choose an answer

electric field

magnetic field

either of them

both of them

Stoke's Law holds for bodies having

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Elliptical shape

Spherical shape

Curved shape

None

The approximate efficiency of Nuclear reactor

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33%

32%

39%

45%

A wire is stretched to double of its length.The strain is

Choose an answer

2

1

Zero

0.5

The law of thermodynamics which discusses the condition under which heat energy is converted into and equivalent amount of work is:

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1st

2nd

3rd

None of these

From the following pairs,choose the pair that does not have identical dimensions

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Angular momentum and Planck's constant

Moment of inertia and Moment of force

Work and Torque

Impulse and Momentum

The splitting of white light into several colors on passing through a glass prism is due to

Choose an answer

Refraction

Reflection

Interference

Diffraction

In case of interference fringes:

Choose an answer

Energy is destroyed at dark

Energy is created at bright fringes

Energy is transferred from dark to bright ringes

None of these

Angular displacement generally expressed in

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Degrees

Revolution

Radian

All of these

The correct unit of power is

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Kilowatt

Dynes

Joule

Kilowatt-hour

The kinetic energy of a body is four times its momentum its velocity is

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2ms^-1

4ms^-1

8ms^-1

16ms^-1

By which principle we can locate the position of new wavefront after a later time?

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principle of irreversibility

principle of light

Archimedes principle

Huygen's principle

T in Kelvin=_______

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273+°C

273-°C

273+°F

273-°F

Total number of base units are

Choose an answer

three

five

seven

nine

Electric potential of earth is takes to be zero because the earth is good

Choose an answer

Semiconductor

Conductor

Insulator

Dielectric

The ability of body to return to its original shape (after the force is removed) is called:

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Elasticity

Ductility

Stress

Strain

Any of these

The angular momentum is a vector quantity with due

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Perpendicular to the axis of rotation

Along the axis of rotation

At the axis of rotation

None of these

One degree of thermodynamics scale of temperature is called:

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Celsius

Fahrenheit

Kelvin

Radian

If the unit of force and length are increased by four times then the unit of energy is increased by

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2 times

4 times

8 times

16 times

At 0k whihc of the following properties of a gas wiil be zero?

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Kinetic energy

Potential Energy

Vibrational Energy

Density

A constant volume gas thermometer works on

Choose an answer

Charles' law

Boyle's law

Pascal's law

None of these

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

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acceptor

donor

either of them

none of them

In thin film colours are due to

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Reflection

Interference

Diffraction

Refraction

A fixed mass of a gas is at a pressure P. if its volume and absolute temperature are both doubled, the new pressure is

Choose an answer

P/4

P/2

P

2P

The total magnification of a combination of two lenses having individual magnification M1 and M2 is

Choose an answer

M₁+ M₂

M₁M₂

M₁- M₂

M₁/ M₂

The equation W = ________𝜟U represents:

Choose an answer

Thermal process

adiabatic process

Isobaric process

None of these

What are the base units of Planks constant h Remember the energy of a photon is given by hf where f element the frequency

Choose an answer

kgms^-1

kgm²s^-1

kgm²s^-2

kgm²s^-3

If water rises 4 cm in a long thin tube because of capillary action then under corresponding conditions of use.the rise (in the tube) of a liquid whose density is 2 g/cm³ will be

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1 cm

2 cm

8 cm

None

The range of the projectile means a body covers horizontal distance which is

Choose an answer

maximum

Minimum

Distance

None of these

Michelson's interferometer is an instrument used to measure the distance with

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Precision

High precision

Extremely high precision

None of these

An electron of charge e coulomb passes through a potential difference of V volts,its energy in 'joules' will be

Choose an answer

V/e

eV

e/V

V

If 'd' is the total displacement of the body in time 't' then the velocity during this interval t is

Choose an answer

Initial velocity

Variable velocity

Average velocity

None of these

A 50 kg man with 20 kg load on his head climbs up 20 steps of 0.25 m height each.The work done in climbing is

Choose an answer

5 J

350 J

100 J

3430 J

A straight current carrying conductor experiences maximum forces in a uniform magnetic field when it is placed:

Choose an answer

Parallel to the field

Perpendicular o the field

At an angle of 45 to the field

None of these

A water hose of internal diameter of 20 mm discharges 30 kg of water in 60 sec. Calculate speed of water

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1.2 ms^-1

1.6 ms^-1

1.8 ms^-1

2.1 ms^-1

The valence energy band may be either

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Completely filled

Partially filled

a and b

All of them

When a body moves in a circular path,no work is done by the force since.

Choose an answer

Force and displacement are perpendicular to each other

The force is always aways from the centre

There is no displacement

There is no net force

Work done by centripetal force is

Choose an answer

Maximum

Minimum

Zero

None

Find the range of the projectile, having speed 30 ms^-1in a direction 30° above the horizon

Choose an answer

50 m

80 m

90 m

100 m

The temperature of sun is measured with

Choose an answer

Platinum thermometer

Gas thermometer

Vapour pressure thermometer

Pyrometer

Pressure exerted by a gas in merely momentum transferred to the walls due to the continuous collisions of molecules of the gas

Choose an answer

Per unit area

Per sec per unit area

Certain area

None of these

Indicate the force / forces which obeys inverse square law

Choose an answer

Strong Nuclear force

Gravitational force

Coulomb's force

b and c

A force passing through the centre of gravity of a body

Choose an answer

Causes translation motion

Causes rotational motion

Produces no motion in the body

Produces both translational and rotational motion

Every point of a wavefront may be considered as a

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Source

Source of wavefront

Source of secondary wavefront

None of these

The subtances which break just after the elastic limit is reached are known as:

Choose an answer

Ductile

Brittle

Malleable

Hard

Soft

For incident angles equal or greater than the critical angle the glass air boundary will act as a

Choose an answer

Convex mirror

Concave mirror

Mirror

None if them

An n-type semiconductor is obtained by doping germanium or silicon with

Choose an answer

Tetravalent impurity

Trivalent impurity

Pentavalent impurity

Monovalent inpurity

The angle subtended at the center of sphere by an area of its surface equal to the half of square of its radius is

Choose an answer

1 sr

2 sr

1/2 sr

none of these

No body begins to move or comes to rest of itself said by

Choose an answer

Thomos Young

Abu Ali Sena

Newton

None of these

The optical fibre is covered for protection with

Choose an answer

rubber jacket

plastic jacket

steel jacket

copper jacket

Dolphins have bodies to assist their movement in water are

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Irregular bodies

Closer to streamline body

Stream lined bodies

None of these

Which of the following is an optical fibre in which the density of central core decreases towards its periphery?

Choose an answer

multi-mode step index fibre

multi-mode graded index fibre

both of them

none of them

If 'd' 'm' and fringe spacing ΔY are known, the interference effect due to light of λ

Choose an answer

Cannot be determine

Can be determined in same cases

Can be determined

None of these

The dimensions of velocity gradient are same as that of

Choose an answer

Frequency

Time period

Angular accelerations

Accelerations

Which of the following is not conservative force

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Electric

Gravitational

Elastic spring force

None

A perpetual motion is that motion which is

Choose an answer

Temporary

Continuous

Forever

None of these

If the focal of a convex lens is 5 cm then to get real and inverted image of the same size as that of object, the object should be placed at

Choose an answer

5 cm

10 cm

15 cm

20 cm

The energy of photon of wavelength 1240 nm is:

Choose an answer

0.5 eV

1.0 eV

1.5 eV

2.0 eV

In a astronomical telescope the final image for normal vision is formed at

Choose an answer

The focal of the eye piece

The least distance of the distinct vision

The focus of the objective lens

Infinity

The electrons in the outermost shell of an atom are called

Choose an answer

Valence electrons

Tightly bound electrons

Free electrons

None of these

Which pair of quantities are not derived quantities?

Choose an answer

Charge, Current

Current, Intensity of Light

solid angle, plane angle

None of these

A single step index fibre can carry more than

Choose an answer

14 TV channels

14,000 phone calls

16 TV channels

a and b

The units of the temperature coefficient of resistant are

Choose an answer

ΩK^-1

K^-1

ΩK

(ΩK)^-1

The burnt gas expelled from the rocket engine with

Choose an answer

High velocity

Extremely high velocity

Very high velocity

None of these

The magnitude of j² in cross product is

Choose an answer

Zero

1

Greater than 1

Less than 0

The modulus of elasticity of material does not depend upon

Choose an answer

Shape

Temperature

Nature of material

Impurities mixed

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

The work done by the system on its environment is considered

Choose an answer

Natural

Positive

Negative

None of these

The materials in which there are plenty of free electrons for electrical conduction are known as

Choose an answer

conductors

insulators

semi-conductors

all of them

A listener observes the frequency “f” of stationary source. If it move toward with 3 times of velocity of sound. Then the apparent frequency of the sound will be

Choose an answer

f

3f

f/2

4f

The only significant motion possessed by the mono-atomic gas molecules is:

Choose an answer

Translatory

Rotatory

Vibratory

None of these

In the study of interference and diffraction, we consider

Choose an answer

plane waves

plane wavefronts

both of them

none of them

A simple astronomical telescope consists of

Choose an answer

Two convex lenses

Three convex and one cocave

Two concave lens

None of these

Einstein inferred that is gravitational acceleration and inertial acceleration are equivalent, gravity must

Choose an answer

Reflect light

Bend light

Turn light

None of these

Optically active substance are those substance which

Choose an answer

Produce polarization of polarized light

Rotate the plane of polarization of polarized light

Produce double refraction

Both a and b

Shear modulus for glass is

Choose an answer

23

39

52

69

When the light waves of the same frequency and amplitude travelling in the same direction superimose each other , they give rise to

Choose an answer

interference

diffraction

dispersion

polarization

Young's modulus for mercury is

Choose an answer

0

2

5

6

The electrical resistance of mercury disappeared below temeprature

Choose an answer

2.1 K

3.4 K

4.1 K

4.2 K

Two forces of 4 dyne and 3 dyne act upon a body.The resultant force on the body can only be

Choose an answer

Between 3 and 4 dyne

Between 1 and 7 dyne

More than 3 dyne

More than 4 dyne

A force of 50 dynes is acted on a body of mass 5 g which is at rest.for and interval of 3 seconds,then impulse is

Choose an answer

0.15 x 10^-3 Ns

0.98 x 10^-3 Ns

1.5 x 10^-3 Ns

2.5 x 10^-3 Ns

Only those processes are probable to take place for which entropy os the system:

Choose an answer

Increases

Remains constant

Both A and B are correct

None of above

How is the image formed by a convex lens affected if the upper half of the lens is covered with a paper

Choose an answer

The upper half of the image is cut off

The brightness of the image is reduce

The brightness of the image is increased

Lower half of the image is cut off

A charge is 90C passes through a wire in 1 hour and 15 minutes. Wat is the current in the wire?

Choose an answer

10mA

20mA

15mA

25mA

At high speed and for long trajectories the air friction is

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Negligible

Equal to gravity

More than gravity

None of these

Breaking load for units area of cross-section of a wire is called:

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Tensile strength

Ductibility

Yield point

Breaking stress

Multimode step index fibre has diameter as

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40 μm

50 μm

60 μm

None of these

The expression of energy stored in an inductor of length L and current I can be expressed by a relation

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1/2 LI²

1/2 I²L

1/2 I²L²

1/2 IL

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

A we go from the equator to the poles, the value of weight

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Remains the same

Increases

Decreases

Decreases up to a latitude of 45°

Young's modulus for aluminium is

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30

70

80

100

Which of the following statements about angular momentums is correct?

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Angular momentum remains conserved

Angular momentum is the product of moment of inertia and angular velocity

Moment of inertia is directly proportional to angular momentum for constant angular speed

All of these

Two light sources obtained from single source are called

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non-coherent sources

coherent sources

monochromatic sources

spherical sources

If the incident light contains different wavelengths the images of each wavelength for a certain value is diffracted in the

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Same directions

Different direction

Opposite direction

None of these

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

The time taken by the light to travel from Pluto to Earth is

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4 hrs 20 sec

5 hrs 20 sec

6 hrs 20 sec

76 hrs 20 sec

How large a force is required to accelerate a body of weight 5 N with 4 ms^-2 is

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10 N

5 N

2 N

1 N

The streamlines are ___________ for an ideal fluid in steady flow

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Perpendicular

Parallel

Anti parallel

Intersect each other

The light source in the transmitter can be

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semiconductor laser

LED

both of them

either of them

The magnitude of vector A,B and C are respectively 12,5 and 13 units and A + B = C then the angle between A and B is

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0

π

π/2

π/4

The speed of light in vacuum is 3 x 10⁸ ms^-1.Its speed in a medium of refractive index 1.5 will be

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6.5 x 10⁸

2 x 10⁸ ms^-1

4.5 x 10⁸ cm

5.5 x 10⁸