Question 1180996
.


I will answer all questions as if they came from Physics.


<pre>
(a)  Use the Law of conservation of mechanical energy.

         mgh = {{{(mv^2)/2}}},

     where m is the mass of the coin.


     Cancel the factor m in both sides and express the maximum height

         {{{h[max]}}} = {{{v^2/(2g)}}} = {{{14.7^2/(2*9.81)}}} = 11 meters (rounded) above the starting height.




(b)  Time of flight  to the upper point  

         {{{t[max]}}} = {{{v/g}}} = {{{14.7/9.81}}} = 1.5 seconds (rounded).


     The total time to fly up and to return to the starting height  {{{t[total]}}} = {{{2*t[max]}}} = 3 seconds  (rounded).




(c)  Velocity when the coin returns to the hand = staring velocity = 14.7 m/s

     due to the Mechanical energy conservation Law.



(d)  Apply the Mechanical energy conservation Law again with the changed value of the final height.
</pre>

Solved, answered and explained.