| 161. | Why do pendulum clocks slow down in summer |
A. Because of the long days of summer | |
B. Due to friction in the coil | |
C. The length of the pendulum increases due to which the time taken for unit oscillation increases. | |
D. The weight of the pendulum increases in summer |
| 162. | If the length of a simple pendulum is increased by 4%, then its time period- |
A. 8%’ will increase | |
B. 2%’ will increase | |
C. 4%’ will increase | |
D. None of these |
| 163. | If the length of the pendulum is made four times, then the time of swing of the pendulum- |
A. Decreases | |
B. Doubles up | |
C. Becomes a quarter | |
D. Becomes four times |
| 164. | When the pendulum is taken to the moon, its time period is- |
A. Will remain the same | |
B. Will decrease | |
C. Will be zero | |
D. Will increase |
| 165. | A particle has mass M and momentum P, its kinetic energy will be- |
A. MP | |
B. P²M | |
C. P²/M | |
D. P²/2M |
| 166. | Hooke’s principle is related to which of the following |
A. By fluid pressure | |
B. Elastically | |
C. Radioactively | |
D. None of these |
| 167. | A small drop of oil spreads on water because – |
A. The viscosity of the oil is high | |
B. Viscosity of water is high | |
C. Surface tension of oil is high | |
D. Water has a higher surface tension |
| 168. | What is the principle of cleaning by soap |
A. Page tension | |
B. Floating | |
C. Viscosity | |
D. Elasticity |
| 169. | Due to which the shape of the rain drop becomes spherical |
A. Viscosity | |
B. Page tension | |
C. Elasticity | |
D. Gravity |
| 170. | The nature of a liquid drop is to take a round shape, due to which- |
A. Page tension | |
B. Viscous force | |
C. Due to upward thrust | |
D. Due to gravity |