In the case of resonance, in forced oscillations

Options

A. amplitude is infinity
B. driving frequency is equal to natural frequency
C. amplitude is zero
D. None of the above

Answer

B

Explanation

For the case of resonance the amplitude is maximum but not infinity. For resonance driving frequency is equal to natural frequency of the system.
The case of a swing is a good example of resonance where a boy push at particular time intervals in a particular way to match the frequency of his push with the natural frequency of swing. In this way he gets maximum possible amplitude.