If a ball that is freely falling has attained a velocity of 19.6 m/s after 2 seconds, what is its velocity 5 seconds later?

68.6 m/s

Explanation:

Recall that the velocity formula to use for accelerated motion due to gravity (g) is:

vf =vi + g * t

so if 19.6 m/s is the initial velocity for the free falling object, then, 5 seconds later under the acceleration of gravity (g) :

vf = 19.6 + 9.8 * (5) = 68.6 m/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.