Wave Optics — Physics STD 12 Science — Question

A curve between magnetic moment and temperature of magnet is

(a)

(b)

(c)

(d)

A nucleus is bombarded with a high speed neutron so that resulting nucleus is a radioactive one. This phenomenon is called

(a) Artificial radioactivity

(b) Fusion

(c) Fission

(d) Radioactivity

When light of wavelength 300 nm (nanometer) falls on a photoelectric emitter, photoelectrons are liberated. For another emitter, however light of 600 nm wavelength is sufficient for creating photoemission. What is the ratio of the work functions of the two emitters

(a) 1 : 2

(b) 2 : 1

(c) 4 : 1

(d) 1 : 4

A very thin film in reflected white light appears:

In a sensitive Wheatstone bridge, current in the galvanometer in the state of slight deflection from the position of balance is:

The reverse biasing in a PN junction diode

(a) Decreases the potential barrier

(b) Increases the potential barrier

(c) Increases the number of minority charge carriers

(d) Increases the number of majority charge carriers

In a transistor:

When neutrons are bombarded on nucleus of , the number of emitted neutrons will be

(a) 1

(b) 2

(c) 3

(d) 4

The accelerations of a particle as seen from two frames S₁ and S₂ have equal magnitude 4m/s².

1. The frames must be at rest with respect to each other.
2. The frames may be moving with respect to each other but neither should be accelerated with respect to the other.
3. The acceleration of S₂ with respect to S₁ may either be zero or 8m/s².
4. The acceleration of S₂ with respect to S₁ may be anything between zero and 8m/s.

Figure shows a horizontal solenoid connected to a battery and a switch. A copper ring is placed on a frictionless track, the axis of the ring being along the axis of the solenoid. As the switch is closed, the ring will: