Answer:
Kinetic friction is an inhibitory force that is present when a body or object begins to move. It should be noted that this force is in the opposite direction to the movement of the body that slides with respect to a surface and parallel to that surface.
In addition, this friction varies according to the surface characteristics and the material properties of the bodies that slide in this surface. Being quantified by the coefficient of kinetic friction 
, which is dimensionless.
Potential: very top of the roller coaster, awaiting the drop. Kinetic: on its way down the largest drop
Answer:
An increase in frequency
Explanation:
A photon is an electromagnetic radiation without mass,as the energy of a photon is increased it frequency also increases.
Consider the equation below.
Energy = hf
We're h= is the Planck constant.
F is the frequency measured in Hertz from this a direct relationship exist between the energy and frequency
