Question

When a bicycle is in motion the force of friction exerted by the ground on the two wheels (front and rear) is $F_1$ and $F_2$ respectively.Then

• A. both $F_1$ and $F_2$ are in backward direction
• B. $F_1$ is in backward direction and $F_2$ is in forward direction
• C. $F_1$ is in forward direction and $F_2$ is in backward direction
• D. both $F_1$ and $F_2$ are in forward direction

Answer 1

The correct option is B $F_1$ is in backward direction and $F_2$ is in forward direction

The frictional force always opposes the direction of motion.

When we peddle the bicycle, the rear wheel moves in the forward direction and the point of contact of wheel and the land surface moves in backward direction hence, forward frictional force ($F_2$) is applied on the rear wheel. The frictional force on the rear wheel causes a transitional motion due to which front wheel moves in the forward direction at its point of contact also moves in the forward direction, hence backward direction ($F_1$) force is applied.

So, $F_1$ is in backward direction and $F_2$ is in forward direction.

The correct option is B.