A bungee jumper attains a speed of 30 m/s just as the bungee cord begins to stretch. If the period of stretch is 2 s while coming to a halt, the jumper's average deceleration is about

Question

Quizplus · Accepted Answer

We can use the formula for average acceleration:

average acceleration = (final velocity - initial velocity) / time taken

Here, the initial velocity is 30 m/s and the final velocity is 0 m/s. The time taken is the period of stretch, which is 2 s.

Therefore, the average acceleration = (0 - 30) / 2 
= -15 m/s^2

Note that the negative sign indicates deceleration.

We can now find the average deceleration as a multiple of acceleration due to gravity (g) using the formula:

average deceleration = (average acceleration) / g

Taking g to be approximately 9.8 m/s^2, we get

average deceleration = (-15) / 9.8 
= -1.53

Rounding off to one significant figure, we get

average deceleration ≈ -1.5

Since the question asks for the magnitude (absolute value) of the average deceleration, the answer would be:

Average deceleration ≈ 1.5 g

which is closest to option C.

A Bungee Jumper Attains a Speed of 30 M/s Just