ok this is the problem i was given however i am going to change the #'s.... please help me see how a problem liek this would be set up and how to go through it so i can understand in order to do it for my actual problem ... thank you sooo much....
a boy ( mass 60 kg) falls from rest and hits the ground. during collision he comes to rest in .0100s the avg. force on him by ground is +15000N. (up is postive) form what height did he fall?
it also says to assume only force is collision due to ground....
please help me set this up and see how to interpret a problem set up in this way thank you so much
2007-02-25 09:53:04 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Might help to understand how the equation F*(deltaT) = m*(deltaV) works. Analyse the units.
Force times time gives you Newton*sec
mass times velocity gives you kg*m/s
So are Newton*sec equivalent to kg*m/s?
From F=m*a, Newtons can also be kg*m/s^2, plug that in to see, yes-they're equivalent.
So what it's saying is: force*(the time it is applied) gives you the change in momentum.
About what sprintdaw... gave you. Formula was good. Algebra, not so much.
F*(deltaT) = m*(deltaV)
15000N*.01s = 60 kg*ΔV
Solve for ΔV. The boy hit the ground and came to rest, so the original velocity = ΔV.
This formula will give you the height h
V^2 = Vo^2 + 2*a*h
where Vo = 0, a=g, V = ΔV from previous step.
2007-02-25 14:29:39 · answer #1 · answered by sojsail 7 · 0⤊ 0⤋
Andre is sweet about all the equations yet bear in thoughts that momentum is a vector quantity. So, we've an initial speed of 28 m/s in a unmarried route and a very last speed of seven.5 m/s interior the different route. The equivalent momentum substitute is then 6.0x10-2 x (28 + 7.5) kg m/s interior the route of the finest speed. Ie. we bumped off the initial momentum and further momentum interior the different route.
2016-12-04 22:51:57 · answer #2 · answered by ? 4 · 0⤊ 0⤋
Ok, the equation for impluse is:
F*(deltaT) = m*(deltaV)
So plugging in the given numbers, (15,000)(60) = (.01)(v),
you can solve for velocity. Using this number, you can use your linear kinematics equations to find the total displacement (how far he fell).
2007-02-25 10:05:20 · answer #3 · answered by sprintdawg007 3 · 0⤊ 0⤋