Which of the following examples describes an increase in potential energy?

a.
a bicycle going down a hill

b.
a basketball falling through a net

c.
a rollercoaster moving down the track

d.
a paint can being carried up a ladder

D.  a paint can being carried up a ladder

Explanation: Potential energy is the energy possessed by an object by virtue of its height.

m= mass

g = acceleration due to gravity

h = height

Thus Potential energy is directly proportional to the height of the body. The greater the height, greater is the potential energy. Thus a paint can being carried up a ladder will lead to increase in potential energy as height will keep on increasing.

f=ma newton's second law 7x8=56n

iron would move it is magnetic there is a mag field around the current in the wire