Online Test

Question # 1

Which of the following properties show light is transverse wave in nature?

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Interference

Reflection

Diffraction

Polarization

A 200 volt, 1000 W bulb is connected across a 1100 volt main supply.The power consumed will be

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1000 W

750 W

500 W

250 W

"Load" is are the device/devices which consume

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Mechanical energy

Electrical energy

Frictional energy

None of these

Conditions for interference are that the two sources should be coherent and

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At a far off distance

Close together

Coinciding

None of these

In d.C. motor, the field coils with the armature coils are connected

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In parallel

In series

Both

None of these

The work function of photoelectric substance is 3.3 eV,The Value of threshold frequency will be

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8 x 10¹⁴ Hertz

5 x 10³³ Hertz

8 x 10¹⁰ Hertz

4 x 10¹¹ Hertz

The phenomenon of electromagnetic induction in which induced

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Current produced

emf produced

Current and emf produced

None of these

When brakes are applied to a fast moving car, the passengers will be thrown:

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Forward

Backward

Downward

None of these

In a standing wave the distance between two adjacent nodes is equal to

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λ/2

λ

3 λ/2

λ/4

The magnitude of motional emf is given by:

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ε = -VBL

ε = VBL

ε = v/BL

ε = - L/VB

The maximum height attained by the projectile is

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V₁²/g sin²θ

V₁²/2g sin2θ

V₁²/2g sin²θ

None

A driver in a lake wants to signal his distress to a person sitting on the edge of the lake flashing his water proof torch He should direct the beam

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Vertically up wards

Horizontally

At angle to the vertical which is slightly less than the critical angle

At an angle to the vertical which is slightly more than critical angle

A common point between OR and AND gates is that

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Their outputs may be 1 even when either of their inputs is at 2

Their outputs are 5 when their all inputs are at 6

Their outputs may be 1 even when either of their inputs is 3

None of these

The relative permitivity for vacuum is

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1

2

1.002

1.004

The energy of a photon is represented by

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h/c²

h/T

hc²

hf/c²

Which of the given pair have same dimension

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Stress, pressure

Elastic modules, pressure

Stress, elastic modules

All have same dimension

The least distance of distinct vision for a normal eye is

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15 cm

25 cm

35 cm

1 m

A capacitor is a perfect insulator for electric

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Direct current

Alternating current

Charge

None of these

Domains are present only in

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Diamagnetic material

Para magnetic material

Ferromagnetic material

All of these

If the object of different masses move with the same velocity, then it is more difficult to stop the

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lighter of the two

massive of the two

any one of them

both of them

An astronaut carries with him a cylinder of capacity 10 litre filled with nitrogen gas at temperature 27°C and pressure 50 atmosphere He makes hole of area 1 cm² in it.In how much time will it be emitted

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755 s

1.132 s

0.153 s

0.387 s

When water is heated from 0C° to 10C° its volume

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Increases

Decreases

Does not change

First decreases and then increases

Maximum dose allowed to general public from artificial sources for year

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500 m Sv

1000 m Sv

1500 m Sv

2000 m Sv

Gauss s law is applicable by considering Gaussian surface The Gaussian surface must has shape which is

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Spherical

Cylindrical

Box type

Any arbitrary closed shape

The electrons are emitted from the metal when light falls on it is of

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High frequency

Low frequency

Suitable frequency

None of these

The ballistic missiles are useful only for

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long ranges

short ranges

medium ranges

none of them

Alternatively increasing and decreasing intensity will be heard when two tuning fork are sounded together is called

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Interference

Beats

Stationary waves

None of these

The velocity of photon is

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3 x 10⁸ ms^-1

3 x 10⁸ cms^-1

3 x 10⁸ cms^-2

The viscosity of liquid is due to

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Adhesive force

Cohesive force

Gravitational force

Diffusion

Successive dark and bright fringes are formed each time the moveable mirror in Michelsion's interferometer is moved a distance

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λ/2

λ/4

λ

3/2λ

If on increasing temperature the resistance decreases,then it is

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Superconductor

Semiconductor

Insulator

None of the above

When a stretched string of length 'I' is plucked form one quarter of its length, the string will vibrate in

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one loop

two loops

three loops

four loops

Which of the following substances possesses the highest elasticity?

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Al

Copper

Steel

Rubber

The potential difference across the depletion region of silicon is

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0.5 V

0.67 V

0.7 V

0.8 V

In a compressional wave, the particles of the medium in the path of the wave move

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perpendicular to the direction of propagation of wave

opposite to the direction of propagation of wave

along the direction of propagation of wave

any one of them

In the self-cross product the angle is

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0°

45°

90°

180°

Newton calculated the velocity of sound in air at S. T. P equal to

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250 ms^-1

280 ms^-1

300 ms^-1

322 ms^-1

Defective cells are generated due to

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Complete destruction of cells

Half destruction of cells

Damaged by radiation but service

None of these

The terminal velocity of a small size spherical body of radius R moving in a fluid varies as

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R

R²

1/R

(1/R)²

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

In place of spark plug, the diesel engine requires also

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High speed air

High temperature air

Low temperature air

None of these