A 4 kg bowling ball rolls at 8 m/s to the right and strikes a 6 kg bowling ball that is rolling at 2 m/s to the left. If the 4 kg ball bounces back with a velocity of 4 m/s to the left, what is the velocity of the 6 kg ball after the collision?

Answer & Explanation:

use the principle of conservation of momentum

take right as positive and left as negative

momentum is the product of mass and velocity

(4 x 8) + (6 x -2) = (4 x -4) + (6 x Y)

32 - 12 = -16 + 6Y

20 + 16 = 6Y

Y = 6m/s

Final answer the velocity of the 6 Kg ball is 6m/s

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.