Question

If neil, weighing 150 pounds, jumps with an initial velocity of 8ft/sec, calculate his hang time on the earth as well as his hang time on the moon, given that the moon has one-sixth the gravitational pull of the earth. then calculate the maximum height of his jump in each location..

Answer 1

we use the following formula to calculate height, 'h', under the effect of gravity: 

h = vt - (1/2)gt^2, where g = 9.8m/s^2 and 't' represents time in seconds

8 ft/s * 0.3048 = 2.4384 m/s

we treat mass as inconsequential to the problem, considering only the effect of initial velocity and gravitational pull

to find his 'hang time' we solve for h=0, knowing that t=0 will be the first value (before the jump): 

0 = 8(0.3048)t - (9.8/2)t^2

solving for 't' we have t=0.497

the 'hang time' will be approximately 0.5 seconds, or 1/2 of a second

the maximum height will be 0.2488m, or 0.816 feet, or 9.8 inches

on the moon, the hang time and height will increase by a factor of 6

hang time: approximately 3 seconds on the moon

maximum height: approximately 2.4 feet