Question

a car and a truck move on a road in the same direction at the same speed. both vehicles slow down with the same stopping force. which statement best explains why the truck needs more distance to stop? a the truck has larger wheels. b the truck has a more powerful engine. c the truck has more mass. d the truck is longer.

Explanation:

According to Newton's second - law $F = ma$ (where $F$ is force, $m$ is mass, and $a$ is acceleration), with the same stopping force $F$, a larger mass $m$ results in a smaller deceleration $a$. Using the kinematic equation $v^{2}-v_{0}^{2}=2ax$ (where $v = 0$ at stop, $v_{0}$ is initial speed, $a$ is acceleration and $x$ is distance), a smaller deceleration $a$ means a larger stopping distance $x$ for the same initial speed $v_{0}$. The truck has more mass than the car.

Answer:

C. The truck has more mass.