How much work would it take to push a # 8 kg # weight up a # 5 m # plane that is at an incline of # pi / 4 #?
The reason work must be done in this situation is that an applied force must act against gravity.
Work done on against (or by) a force is defined by
You need to notice that in a problem such as this, the angle of the incline (and therefore of
That said, this time, both angles would be
The work done is