- #1

chronos98

- 14

- 0

## Homework Statement

A 2.0 kg block rests on a frictionless wedge that has a 60 deg incline and an acceleration [tex]\vec{a}[/tex] to the right such that the mass remains stationary relative to the wedge. a) Draw the free-body diagram of the block and use it to determine the magnitude of the acceleration.

## Homework Equations

F=ma

**3. Picture on right. My attempted diagram on left**

http://img707.imageshack.us/img707/2420/physicsm.jpg

Uploaded with ImageShack.us

## The Attempt at a Solution

So my main problem is determining what forces are acting on the block, and drawing the diagram. When I tried it, I thought that the normal force would be increased due to the acceleration of the wedge, but I am certain I have done this wrong. So, I drew a diagram of forces acting on the block which I said were the normal force, perpendicular to the wedge, and the force of gravity acting downwards. My coordinate system was setup so gravity pointed in the -y direction, and x was pointing straight to the right. I said that [tex]\sum(F_x)=F_n*\cos(30)=(2.0 kg)*\vec{a}[/tex] and [tex]\sum(F_y)=F_n*\sin(30)-F_g=0[/tex]. I used the summation of forces in y to find the normal force, which I plugged into the first to find acceleration. I got a normal force of 39.24N and an acceleration of 16.9914 m/s/s.

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