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1. The problem statement, all variables and given/known data

1. The problem statement, all variables and given/known data

A flat-bed truck with a frictionless ramp accelerates forward.

(That 35 is the angle, and a 5kg block rests on the hypotenuse)

/ |

--- / l

- - /35deg l

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-o-----------0--

The acceleration of the truck is suck that a 5.0kg block is stationary (relative to the ramp). If the rolling coefficient of friction is (mew=0.10) Find the force the engine is exerting on the 12000kg truck.

2. Relevant equations

F=ma Ff=mewFn Fg=mg

3. The attempt at a solution

Well...frankly, I really don't know how to start this question. How do I know where to start first? I'm wondering if I need acceleration in this or not, but I got a=0.98 m/s2 assuming that the truck's accel and the box's are the same.

Ok, so I reattempted it finding Fparallel as 40.138N assuming Fparallel is = to Fn

I found Ff as 4.0138N, and looked for Fperpendicular which = to 28.105N

I subracted Ff from Fperpendicular to find Fnet which I got as 24.09.

I took the Fnet and divided by the mass of the crate which is 5kg on the ramp which got me 4.82m/s2

Assuming that the acceleration of the box, and the acceleration of the truck to be the same,

I did Fnet=ma which is Fnet=12000 x 4.82 = 56840N

It's a pretty big number, and I'm wondering if anyone can help me confirm if I did it right.

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# Homework Help: Dynamics, please help me start this.

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