Electrostatic Potential and Capacitance — Physics STD 12 Science — Question

Einstein got Nobel prize on which of the following works

(a) Mass-energy relation	(b) Special theory of relativity
(c) Photoelectric equation	(d)  (a) and (b) both

A person A can clearly see objects between 25cm and 200cm. Which of the following may represent the range of clear vision for a person B having muscles stronger than A, but all other parameters of eye identical to that of A?

1. 25cm to 200cm.
2. 18cm to 200cm.
3. 25cm to 300cm.
4. 18cm to 300cm.

In the hysteresis cycle, the value of H needed to make the intensity of magnetisation zero is called

(a) Retentivity

(b) Coercive force

(c) Lorentz force

(d) None of the above

The direction of electric field is from:

In the Boolean algebra, the following one is wrong:

X-ray beam can be deflected:

Four capacitors of each of capacity 3μF are connected as shown in the adjoining figure. The ratio of equivalent capacitance between A  and B  and between A  and C  will be

(a) 4 : 3

(b) 3 : 4

(c) 2 : 3

(d) 3 : 2

Consider a sample of a pure beta-active material:

1. All the beta particles emitted have the same energy.
2. The beta particles originally exist inside the nucleus and are ejected at the time of beta decay.
3. The antineutrino emitted in a beta decay has zero mass and hence zero momentum.
4. The active nucleus changes to one of its isobars after the beta decay.

If the current is doubled, the deflection is also doubled in

(a) A tangent galvanometer	(b) A moving coil galvanometer
(c) Both (a) and (b)	(d) None of these