A race car will make one lap around a circular track of radius R. When the car has traveled halfway around the track, what is the magnitude of the car's displacement from the starting point?
A)2R
B)R
C)$\pi$R
D)2$\pi$R
E)zero meters

Question

Quizplus · Accepted Answer

When the car has traveled halfway around the circular track, it is at the point directly opposite the starting point on the circle. The displacement is the straight-line distance between the starting point and this point, which is the diameter of the circle, equal to 2R.

A Race Car Will Make One Lap Around a Circular π\piπ

A Race Car Will Make One Lap Around a Circular $\pi$