In your own words, explain the following terms: i. normal reaction. ii. static friction. iii. kinetic friction. iv. co-efficient of friction

I. is a force that exerts a surface on a body that is supported by it.

II. are imperfections on contact surfaces and the perpendicular force that holds the two surfaces together.

III. the rubbing of force that acts against moving bodies.

IV. inert body, two objects that are not moving

Explanation:

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.