Acceleration of box pulled at 23.9° above horizontal

[black_hole]

Homework Statement

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.

Homework Equations

The Attempt at a Solution

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

 

[conana]

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

 

[ideasrule]

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