Question

A 1260-kg car is pushing an out-of-gear 2180-kg truck that has a dead battery. When the driver steps on the accelerator, the drive wheels of the car push horizontally against the ground with a force of 4480 N. The rolling friction of the car can be neglected, but the heavier truck has a rolling friction of 755 N, including the 'friction' of turning the truck's drivetrain. What is the magnitude of the force the car applies to the truck?

Answer 1

The force that the car applies to the truck is the total force the car exerts against the ground minus the truck's rolling friction, which equates to 3725 N.

Step-by-step explanation:

The student is asking about the force exerted by a car on a truck it is pushing. The car exerts a force of 4480 N against the ground, and the truck experiences a rolling friction force of 755 N. To find the force the car applies to the truck, we must consider Newton's second law of motion, which states that the net force acting on an object is equal to the product of the object's mass and its acceleration (F = ma).

Since the car and truck are being treated as a single system and the rolling friction of the car is negligible, the only opposing force we need to consider is the rolling friction of the truck. To move both car and truck, the force that the car applies to the truck is the total force it exerts minus the rolling friction experienced by the truck.

The force applied by the car on the truck is therefore 4480 N - 755 N = 3725 N.