Question

The graph shows the distance y, in inches, a pendulum moves to the right (positive displacement) and to the left (negative displacement), for a given number of seconds x. How many seconds are required for the pendulum to move from its resting position and return?

Answer 1

1 second

Explanation:

1.5 seconds - 0.5 seconds = 1 second

Answer 2

1 second.

Explanation:

The graph is showing a periodic movement, which is the case of the movement of a pendulum. The x-axis represents the equilibrium point, that is y=0. So, each extreme point is where the pendulum immediately stops an return, So, we just have to observe what time it takes intercepting the axis twice in a row.

So, we see that at x=0.5, the pendulum is at equilibrium point, then at x=1.5 is crossing immediately again the equilibrium point. The time that took from 0.5 to 1.5 is 1 second, that is, 1.5-0.5 = 1 second.

Therefore, it takes 1 second to move from its resting point and return.