Question

An object is released from rest. The time it takes to fall through a distance h and the speed of the object as it falls through this distance are measured with a pendulum clock. The entire apparatus is taken on the moon and the experiment is repeated
(a) the measured times are same
(b) the measured speeds are same
(c) the actual times in the fall are equal
(d) the actual speeds are equal

Answer 1

Explanation:

• (a) The measured times are same and (b) the measured speeds are same.  We know that $g^'=g/6$ where $g^{\prime}$ is the acceleration due to gravity in moon and g is the acceleration due to gravity in earth.  
• This shows that the acceleration due to gravity is greater in earth than that in moon.
• Therefore, the effect of gravity can affect the actual quantity where as it cannot affect the measured quantity.
• Thus, the clock will show the same time resulting in the same speed.