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## Homework Statement

In the figure, a crate of mass m = 107 kg is pushed at a constant speed up a frictionless ramp (θ = 32°) by a horizontal force [URL]http://edugen.wiley.com/edugen/shared/assignment/test/session.quest1510980entrance1_N10037.mml?size=14&rnd=1298229739658 [Broken][/URL].[/URL] The positive direction of an x axis is up the ramp, and the positive direction of a y axis is perpendicular to the ramp. (a) What is the magnitude of [URL]http://edugen.wiley.com/edugen/shared/assignment/test/session.quest1510980entrance1_N10037.mml?size=14&rnd=1298229739658 [Broken][/URL]?[/URL] (b) What is the magnitude of the normal force on the crate?

http://edugen.wiley.com/edugen/courses/crs4957/art/qb/qu/c05/q32.jpg

**2. The attempt at a solution**

I just wanted to see if this is right, I am very confused on Newton's Laws but from staring at this for hours I came up with:

F(perpendicular)= m.g.cosθ= Fy

Fy= (107kg)(9.8 m/s^2)cos(32)=72.2 N which would be the answer to part (b)? Because the crate is not moving in the y direction, the forces must cancel each other out and the normal force acting on the crate would be 72.2 N?

for part (a):

F(parallel)= m.g.sinθ= Fx

Fx= (107kg)(9.8m/s^2)sin(32)= 36.8 N

Since the crate is also not moving in the x direction (up the slope), the force pushing the on the crate, [URL]http://edugen.wiley.com/edugen/shared/assignment/test/session.quest1510980entrance1_N10037.mml?size=14&rnd=1298229739658[/URL] would have to equal the force that is acting on the crate in the -x direction, in other words the answer to part (b) would be 36.8 N?

I'm out of attempts on my homework and wanted to make sure it was okay before I entered the solution, any feedback would be wonderful! Thanks c:

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