SOLUTION: A boy tosses a coin upward with a velocity of +14.7m/s. Find (a) the maximum height reached by the coin, (b) time of flight, and the (c) velocity when the coin returns to the

Question 1180996: A boy tosses a coin upward with a velocity of +14.7m/s. Find
(a) the maximum height reached by the coin,
(b) time of flight, and the
(c) velocity when the coin returns to the hand.
(d) Suppose the boy failed to catch the coin and the coin goes to the
ground, with what velocity will it strike the ground? The boy's hand is
0.49m above the ground.
Found 2 solutions by ikleyn, Edwin McCravy:
Answer by ikleyn(52817) (Show Source): You can put this solution on YOUR website!
.

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

(a) Use the Law of conservation of mechanical energy. mgh = , where m is the mass of the coin. Cancel the factor m in both sides and express the maximum height = = = 11 meters (rounded) above the starting height. (b) Time of flight to the upper point = = = 1.5 seconds (rounded). The total time to fly up and to return to the starting height = = 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.

Solved, answered and explained.

Answer by Edwin McCravy(20060) (Show Source): You can put this solution on YOUR website!

I think you should use the four standard equations of motion, and be careful that upward vector quantities are positive and downward ones are negative. The tutor above failed to observe this convention.
A boy tosses a coin upward with a velocity of +14.7m/s. Find
(a) the maximum height reached by the coin,
Answer: 11.515 m
(b) time of flight
Answer: 3 seconds.
(c) velocity when the coin returns to the hand. (The boy's hand is 0.49m above
the ground.)
That's the velocity that's equal in magnitude but opposite in direction velocity as the velocity when it left his hand. Answer: -14.7 m/s
(d) Suppose the boy failed to catch the coin and the coin goes to the ground,
with what velocity will it strike the ground?
We take the negative square root because the final velocity is downward. Answer: -15.02 m/s Edwin

RELATED QUESTIONS
A soccer ball was hit and moved upward at a 50.0° angle with an initial velocity of 40.0 (answered by ikleyn)
A soccer ball was hit and moved upward at a 50.0° angle with an initial velocity of 40.0 (answered by ikleyn)
A soccer ball was hit and moved upward at a 50.0° angle with an initial velocity of 40.0 (answered by ikleyn)
a toy rocket is launched upward from ground level with an initial velocity of 51 meters... (answered by ikleyn)
A toy rocket is launched upward from ground level with an initial velocity of 39 meters... (answered by lwsshak3)
If a baseball is projected upward from ground level with an initial velocity of 96 feet... (answered by robertb)
from 4 feet above the ground, Maya throws a ball upward with the velocity of 18 feet per... (answered by richwmiller)
a coin is dropped from a height of 750 feet. the height,s,at time,t, is given by... (answered by stanbon)
MAXIMUM HEIGHT. If a baseball is projected upward from ground level with an intial... (answered by venugopalramana)