In which of the following figures shown, will the sound of a tuning fork hit with rubber pad at end A be heard maximum at end B?

1. I
2. II
3. Both I and II
4. Cannot be decided

The force of 20 N is applied at distance of 40 cm from the axis. The moment of force is

1. 8 N-m
2. 0.4 N-m
3. 8.5 N-m
4. 20 N-m

In a radioactive decay, the atomic number of parent nuclei is not changed. The radiation emitted will be

1. β-rays
2. γ-rays
3. α-rays
4. the atomic number is affected by all forms of radioactive decay