Q29DQ A small compact car is pushing a... [FREE SOLUTION]

91影视

University Physics with Modern Physics

Hugh D. Young, Roger A. Freedman

Physics

14th edition Edition 路 1596 pages

ISBN: 9780321973610

Chapter 1: Q29DQ (page 123)

A small compact car is pushing a large van that has broken down, and they travel along the road with equal velocities and accelerations. While the car is speeding up, is the force it exerts on the van larger than, smaller than, or the same magnitude as the force the van exerts on it? Which vehicle has the larger net force on it, or are the net forces the same? Explain.

Short Answer

Expert verified

The force that the car exerts on the van is the same in magnitude as the force exerted by the van on the car. As $鈭� \overset{鈫�}{F} = m \overset{鈫�}{a}$ and the accelerations are the same; hence, the net force on the van will be larger than that on the car.

Step by step solution

Newton’s 3rd law

The first body exerts a force on the second body, and the second body exerts an equal and opposite force on the first body.

${\overset{鈫�}{F}}_{12} = - {\overset{鈫�}{F}}_{21}$

This action and reaction of forces act on different bodies. These forces act on each other as long the objects are in contact.

The given case

As the car and the van have equal velocities and acceleration, according to Newton鈥檚 3^rd law, the force thatthe car exerts on the van is the same in magnitude as the force exerted by the van on the car. As $鈭� \overset{鈫�}{F} = m \overset{鈫�}{a}$ and the accelerations are the same; hence, the net force on the van will be larger than thaton the car because the mass of the van is larger than that of the car.