The period of a simple pendulum is measured to be 4.0 seconds in a frame of reference. Which of the following is correct when the period of the pendulum is measured by an observer moving with 0.4 times the speed of the light?
Choose one answer.
a. The time period of the pendulum remains constant.
b. The time period of the pendulum decreases.
c. The time period of the pendulum increases.
d. The time period of the pendulum decreases by half.
Answer = a.
To answer this question, we first need to understand the concept of time dilation in special relativity. Time dilation refers to the phenomenon where the time interval between events is observed to be different by observers in different reference frames, particularly when one of the frames is moving at a significant fraction of the speed of light.
In this case, the observer is moving with 0.4 times the speed of light relative to the frame of reference where the period of the pendulum is measured to be 4.0 seconds.
According to the theory of special relativity, as an observer approaches the speed of light, time dilation occurs, meaning that their perception of time slows down relative to an observer at rest. This means that when the observer is moving at high speeds, the time period of the pendulum as measured by them will appear to be longer compared to an observer at rest.
So, the correct answer is c. The time period of the pendulum increases.