Online Test

Question # 1

At the maximum height the V_fis

Choose an answer

Constant

Zero

Maximum

None of these

A tube closed at one end containing air, produces, when excited, the fundamental note of frequency in Hz given that / = 1 m and V = 640 ms^-1

Choose an answer

256

128

512

160

The winding of the electromagnet, is called

Choose an answer

coil

magnetic field

field coil

none of them

If the angle of refraction is 90^o, for which the angle of incidence is called

Choose an answer

Incident angle

Critical angle

Angle of emergence

None of these

The ratio of volume stress/volume strain is called as

Choose an answer

modulus

Bulk modulus

shear modulus

Young's modulus

RBE of Neutrons and protons below 10 MeV is

Choose an answer

0.5 RBE

10.0 RBE

0.8 RBE

1.7 RBE

George Stoke found the effect of viscous drag on small sphere falling through liquids in

Choose an answer

1782

1851

1902

1947

Unit of permeability of free space is

Choose an answer

Wba^-1 m^-1

NmA^-1

Nm°A^-2

Both a & c

A steel bar can bear a load of 20 tons. If the thickness of bar is double, then for the same depression it can bear a load of:

Choose an answer

40 ton

80 ton

160 ton

5 ton

The mass of eachα-particle is nearly

Choose an answer

Twice times the mass of hydrogen atom

Three times the mass of hydrogen atom

Four times the mass of hydrogen atom

Five times the mass of hydrogen atom

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

Choose an answer

Reversible

Irreversible

Sometimes A and B

None of these

Swimming is possible on account of

Choose an answer

First law of motion

Second law of motion

Third law of motion

Newtons law of gravitation

The original source of geothermal energy is

Choose an answer

Biomass

Fossil fuels

Moon

Earth

The periodic waves are those which are

Choose an answer

Continuous

Regular

Rhythmic disturbance

All of these

At higher temperature, the body emits short wavelengths in the region

Choose an answer

Infra red

Ultraviolet

Far-infra red

None of these

P-type crystal of a p-n junction diode is connected to a positive terminal of battery and n-types crystal connected to negative terminal of battery

Choose an answer

Diode is forward based

Diode is reverse biased

Potential barrier in depletion layer increases

Potential barrier in depletion layer remains unchanged

If the metal bob in a simple pendulum is replaced by a wooden bob,then its time period will

Choose an answer

Increase

Decrease

Remain the same

First A then D

The work done by the system on its environment is considered

Choose an answer

Natural

Positive

Negative

None of these

The SI units of displacement is

Choose an answer

m

kg

ms^-1

None of these

The difference between 1st ring fringe and 1st dark fringe is measured as

Choose an answer

λD/2d

λD/d

λD/4d

2λD/d

For glass-air boundary, the value of the critical angle is

Choose an answer

42°

45°

30°

60°

The electromagnetic force is long-range and causes

Choose an answer

Physical phenomenon

Chemical reactions

Can produce new product

None of these

Range of β-particle in air is

Choose an answer

10 cm

1 meter

Several meters

None of these

The torque acting upon a system is zero Which of the following will be conserved

Choose an answer

Linear momentum

Angular momentum

Moment of inertia

Angular velocity

On the ground the gravitational force on a satellite is W. What is the gravitational force on the satellite when at a height R/50,where R is the radius of the Earth

Choose an answer

1.02 W

1.00 W

0.98 W

0.96 W

The particles equal in mass or lighter than protons are

Choose an answer

Baryons

Mesons

Leptons

None of these

Electron was discovered by

Choose an answer

R.(A) Millikan

J.J. Thomson

W. Crooks

Einstein

The value of Boltzman constant is

Choose an answer

1.28 x 10^-22JK^-1

1.38 x 10^-23JK^-1

1.38 x 10^-28JK^-1

1.35 x 10^-29JK^-1

In p-type semiconductor

Choose an answer

Major current carrier is electrons

Major carrier is mobile negative ions

Major carrier is mobile holes

The number of mobile holes exceeds the number of acceptors

The field inside the solenoid is

Choose an answer

Weak

Strong

Very strong

None of these

The lowlying Earth satellites have acceleration

Choose an answer

9.7 ms^-2

9.9 ms^-2

10.0 ms^-2

9.8 ms^-2

In common emitter amplifier. When small signal voltage is applied at the input it changes the voltage at

Choose an answer

base

Emitter

Collector

None of these

A heater coil rated at (1000W -200 V) is connected to 110 volt line what will be the power consumed?

Choose an answer

200 W

302.5 W

250 W

350 W

The velocity of a body at some particular instant is called

Choose an answer

Initial velocity

Instantaneous velocity

Variable velocity

None of these

A radioactivity element dissolved in a liquid and the solution is heated the activity of the solution

Choose an answer

Is smaller than that of the element

Is greater than that of the element

Is equal to that of the element

Will be smaller or greater depending upon whether the solution is weak or concentrated

The resolving power of telescope depends on

Choose an answer

Focal length of eye lens

Focal length of objective lens

Length of the telescope

Diameter of he objective lens

For the treatment of skin cancers, the isotopes/isotopes are used

Choose an answer

Phosphorous-32

Strontium-90

Both

None of these

If the focal length of objective is 10 mm find its magnification

Choose an answer

18

19

20

21

If no external torques act, the angular momentum of a body rotating about a fixed axis in two dimensions is

Choose an answer

Variables

Constant

Non conserved

None

For a motor which is over loaded the magnitude of back emf

Choose an answer

becomes zero

get decreased

get increased

remains constant

α,β andγ rays are emitted form a radio-active substance

Choose an answer

spontaneously

when it is heated

when it is exposed to light

when it interacts with the other particle