Question

question 18. padma is riding a bike down a hill. as she gets to the bottom, she applies the brakes to stop the bikes forward motion. which of the following statements best describes an example of both the frictional force and the normal force acting on the bike? a. padmas body pressing down on the seat of the bike is an example of frictional force and the ground pushing up on the bike is an example of normal force. b. the ground pushing up on the bike is an example of frictional force and padmas body pressing down on the seat of the bike is an example of normal force. c. padmas hand squeezing the handle of the brake is an example of frictional force and the surface of the brake rubbing the rim of the front tire is an example of normal force. d. the surface of the brake rubbing the rim of the front tire is an example of frictional force and padmas body pressing down on the seat of the bike is an example of normal force.

Explanation:

Frictional force resists relative motion (body - seat contact). Normal force is perpendicular to the surface (ground - bike).

Answer:

A. Padma's body pressing down on the seat of the bike is an example of frictional force and the ground pushing up on the bike is an example of normal force.