The time period of a 1 m long pendulum approximates to

The length of a simple pendulum is increased four times to its previous value while the mass is doubled. What is the ratio of the new and previous time period of the pendulum?

Which one of the following statements regarding simple pendulum is correct ? Simple pendulum has a time period independent of amplitude :

A ball is thrown vertically upward with a speed of 40 m/s. The time taken by the ball to reach the maximum height would be approximately

A tennis ball is thrown in the vertically upward direction and the ball attains a maximum height of 20 m. The ball was thrown approximately with an velocity of

The working principle of a washing machine is :