Acar traveling at 39 m/s starts to decelerate steadily. it comes to a complete stop in 9 seconds. what is its acceleration?

Acceleration = (change in speed) / (time for the change)

Change in speed = (end speed) - (start speed) = (zero - 39 m/s) = -39 m/s

time for the change = 9 seconds

Acceleration = (-39 m/s) / (9 seconds)

Acceleration = -4.33 m/s²

d. platinum would have the greatest temperature increase because it has the lowest specific heat.

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.