Suppose you are preparing an actual-size trajectory diagram of a freely falling object. The time interval between positions is $0.02 \mathrm{~s}$. How long should you draw the acceleration arrows on your diagram?
A) $9.8 \mathrm{~m}$
B) $0.20 \mathrm{~m}$
C) $0.04 \mathrm{~m}$
D) $3.9 \mathrm{~cm}$
E) $0.39 \mathrm{~cm}$
F) Other (specify)

Question

Quizplus · Accepted Answer

The acceleration due to gravity is $9.8 \mathrm{~m/s^2}$. For a time interval of $0.02 \mathrm{~s}$, the change in velocity is $9.8 \times 0.02 = 0.196 \mathrm{~m/s}$. To represent this on a diagram, a reasonable scale would be $1 \mathrm{~m/s}$ per $2 \mathrm{~cm}$, making the arrow $0.39 \mathrm{~cm}$ long.

Suppose You Are Preparing an Actual-Size Trajectory Diagram of a Freely