Two pendulums of length and start vibrating in phase. At some instant, the two are at their mean position in the same phase. The minimum number of vibrations of the shorter pendulum after which the two are again in phase at the mean position is:
- A11
- B9
- C10
- D8
Solution & Step-by-step Explanation
Time period .
Let be vibrations of longer pendulum and be vibrations of shorter pendulum. For them to be in phase:
The minimum vibrations of the shorter pendulum () is .
Let be vibrations of longer pendulum and be vibrations of shorter pendulum. For them to be in phase:
The minimum vibrations of the shorter pendulum () is .