# Forces Problems

1. Jan 11, 2010

### black_hole

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

A student pulls a box of books on a smooth horizontal floor with a force of 138 N in a direction of 23.9° above the horizontal. If the mass of the box and the books is 51.6 kg, what is the acceleration of the box?

A constant force of 2.2 N is required to drag a 49.2 kg box across a rough wooden floor at a constant speed of 2.2 m/s. Find the coefficient of sliding friction between the floor and the box.

A 12.6 kg bucket is lowered vertically by a rope in which there is 127.6 N of tension at a given instant. What is the acceleration of the bucket? When giving you answer, assume the acceleration is positive if up and negative if down.

2. Relevant equations

3. The attempt at a solution

I was able to draw force diagrams, but that's all.

2. Jan 11, 2010

### conana

Now use those force diagrams to write out F=ma equations, separating your force vectors into horizontal and vertical components.

3. Jan 11, 2010

### ideasrule

Next, write out Newton's second law for both the x and y directions.