A force does work on an object if a component of the force is called

Explanation:

The work done by an object is given by :

Here,

F is force

d is displacement

is the angel between F and d.

If the angle between force and displacement is 0, then the work done is equal to, .

So, a force does work on an object if a component of the force is parallel to the displacement of the object.    

the first american roller coaster was the mauch chunk switchback railway, built in the mountains of pennsylvania in the mid-1800s. the track, originally built to send coal to a railway, was reconfigured as a "scenic tour."

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.