1) If a bus travelling at 20 m/s is subject to a steady deceleration of 5 m/s2, how long will it take to come to rest?

Bus will take 4 seconds before it comes to rest.

Explanation:

Initial Velocity  of bus = u = 20 ms⁻¹

Final Velocity of bus = v = 0 ms⁻¹

Deceleration of bus = a = -5 ms⁻²

Time taken by bus before it comes to rest = t = ?

Using the equation formula

a = (v - u)/t

-5 = (0 - 20) / (t)

t = -20/-5

t = 4 sec

Therefore, Bus will take 4 seconds before it comes to rest.

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.