A weight watcher who normally weighs 400 N stands on top of a very tall ladder so she is one Earth radius above the Earth's surface.How much would she weigh there?
A)0
B)100 N
C)200 N
D)400 N
E)none of these

Question

Quizplus · Accepted Answer

When the weight watcher is one Earth radius above the Earth's surface, she is twice as far away from the Earth's center as compared to her usual position. This means that the gravitational force on her will be reduced to one-fourth of its usual value. Therefore, her weight will be (1/4) of her usual weight, which equals 100 N. So, the correct choice is B.

A Weight Watcher Who Normally Weighs 400 N Stands on Top