A 1230 kg car pushes a 2160 kg truck that has a dead battery. When the driver steps on the accelerator, the drive wheels of the car push against the ground with a force of 4590N . Take the friction between the truck's tires and the ground to be 470N .

What is the magnitude F_ConT of the force that the car exerts on the truck? Use the coordinate system shown in Part B, where upward is the positive y direction and to the right F_ConT points, is the positive x direction.

Question

A 1230 kg car pushes a 2160 kg truck that has a dead battery. When the driver steps on the accelerator, the drive wheels of the car push against the ground with a force of 4590N . Take the friction between the truck's tires and the ground to be 470N . 

What is the magnitude F_ConT of the force that the car exerts on the truck? Use the coordinate system shown in Part B, where upward is the positive y direction and to the right F_ConT points, is the positive x direction.

anonymous · Answer

http://session.masteringphysics.com/problemAsset/1060044/28/1060044FBDa.jpg This the free body diagram for Car and truck. I still don't understand why the friction force is in the positive direction for the car.

anonymous · Answer

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