XII A Physics Priliminary

When electric flux passes through any surface, then all of the following are the factors on which it depends EXCEPT the:

a) Area of the surface

b) Nature of the surface

c) Intensity of the electric field

d) Direction of the surface relative to the electric field

• a

• b

• c

• d

The range of wave length of radiation emitted by a hot body at different temperature is:

a) Infinite

b) Discrete

c) Continuous

d) Discontinuous

• a

• b

• c

• d

In daily life the relative change in mass, length and time of an object cannot be observed because the:

a) Size of the object is very small

b) Mass of the object is very large

c) Speed of the object is equal to the speed of light

d) Speed of the object is much smaller than that of light

• a

• b

• c

• d

In the forward biasing, the resistance offered by a p – n junction diode:

a) Is low

b) Is zero

c) Is high

d) Is varies

• a

• b

• c

• d

If the object moves with speed of light, its mass become:

a) Zero

b) Infinity

c) Remain same

d) Decrease

• a

• b

• c

• d

The gain of non – inverting op – amp depends on:

a) Internal resistance

b) External resistance

c) Potential difference

d) Current

• a

• b

• c

• d

• a

• b

• c

• d

If the resistance of a galvanometer is 50 ohms, the resistance of ammeter having a 0.1 shunt resistance will be:

a) 50.1 ohms

b) 5.01 ohms

c) 0.501 ohms

d) 0.01 ohms

• a

• b

• c

• d

Potentiometer can be used as:

a) Ohmmeter

b) Ammeter

c) Galvanometer

d) Potential divider

• a

• b

• c

• d

In the given circuit the current through the battery is:

a) 0.5 A

b) 1 A

c) 1.5 A

d) 2 A

• a

• b

• c

• d