# Statics: Equilibrium and circular lawn roller

1. Oct 10, 2008

### TranceMaster

1. What horizontal force F will pull the 100 kg lawn roller over the step? What is the value of F if it is directed normal to AC?

I cant draw a picture for you, but i can describe it. There is a circular lawn roller in contact with a step that is 3cm in height. The roller is currently resting on the ground. the radius of the roller is 30 cm. I initially need to find a force in the horizontal direction, then find a force that is 45 degrees up from that. You can mark the top of the step as point A and the center of the roller as point C. Both forces start from C.

2. Relevant equations

sum F = 0
sum M = 0

3. The attempt at a solution

I tried solving for the force in both the X and Y directions. My professor gave me the hint that as the roller is goin up the step, the normal force will end up disappearing from the ground to the step. This however, still has me confused. He told me that i will have 2 unknowns and 2 equations. I have the equations, but I am uncertain of what I am doing to get the force.

2. Oct 10, 2008

### Staff: Mentor

Hint: As the roller climbs the step it must rotate about the edge of the step. Consider torques about that point.