The maximum displacement of bob from its mean position on either side is called :

1. Period of oscillation
2. Frequency of oscillation
3. Amplitude
4. Oscillation

A simple pendulum is made by suspending a bob of mass 1 kg by a string of length l. Now if the length of this pendulum is increased to 4l, then its time period T will :

1. remain the same
2. become twice
3. become four times
4. become half

The time period of a seconds' pendulum clock is —

1. 1 s
2. 2 s
3. 1 min
4. 12 h