(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 1000 kg car pushes a 2000 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 4500 N. Rolling friction can be neglected.

2. Relevant equations

F=ma

acceleration of car = acceleration of truck

3. The attempt at a solution

I have determined that both the car and the truck must move at the same acceleration. The car pushes off the ground with 4500N, so that:

F = ma

4500 = (1000)a

a = 4.5 m/s^2

I attempted to solve for F on the truck:

F = ma

F = (2000)(4.5)

F = 9000

But this is incorrect. Should I be combining the masses so that F = (3000)(4.5)? Or am I just way off here?

I am struggling to put together the proper free-body diagram and I think its messing up my understanding of what force is on what object. A push in the right direction is appreciated! Pun intended.

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# Homework Help: Newton's Third Law: A Car Pushes A Truck

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