A girl walks on a level floor in a straight line in the +x direction.Her foot exerts a force on the floor.The direction of the reaction force by the floor on her foot is in
A)+x direction
B)-x direction
C)+y direction (vertically up)
D)-y direction (vertically down)
E)depends how fast she is walking

Question

Quizplus · Accepted Answer

The reaction force by the floor on her foot is in the -x direction because it is the force that opposes the force exerted by her foot on the floor.

A Girl Walks on a Level Floor in a Straight