Asked by Charles
A body of mass 20kg falls from rest through a height of 10m and comes to rest having penerated a distance of 9.8m into sandy ground calculate the average force exerted by the sand in bringing the body to rest(take g=10m/s^2)
Answers
Answered by
Anonymous
get crash speed
(1/2) m v^2 = m g h
v = sqrt (2 g h) (but you knew that, right?)
v = sqrt (2*9.81*10) = 14 meters/second
momentum at crash = m v = 20 * 14 = 280 kg m/s
calculate time to stop
average stop speed = 7 m/s
stop distance = 9.8 meters
t = stop time = 9.8 m / 7 m/s = 1.4 seconds
average force = change of momentum / time to stop = 280 /1.4 = 200 Newtons
(1/2) m v^2 = m g h
v = sqrt (2 g h) (but you knew that, right?)
v = sqrt (2*9.81*10) = 14 meters/second
momentum at crash = m v = 20 * 14 = 280 kg m/s
calculate time to stop
average stop speed = 7 m/s
stop distance = 9.8 meters
t = stop time = 9.8 m / 7 m/s = 1.4 seconds
average force = change of momentum / time to stop = 280 /1.4 = 200 Newtons
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.