"The kinetic friction between a 90 kg object and a horizontal surface is 350 N. If the initial speed of the object is 20 m/s, what is the distance the object will slide before coming to a stop?"
The answer is 51.4 m, but could someone please provide an explanation as to why that is? Thank you!
The answer is 51.4 m, but could someone please provide an explanation as to why that is? Thank you!
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work out acceleration which will be negative (since it's slowing down) and the time it takes to reach 0 m/s.
F = ma where F = 350N, m = 90 so a = -3.89m/s/s
v = u + at so we are trying to find t when v = 0. Since u = 20m/s and a = -3.89,
t = 5.14 seconds
s = ut + .5at^2 so we know that u = 20m/s, a = -3.89m/s/s and t = 5.14s
therefore,
s = 20*5.14 + .5*-3.89*5.14^2
This gives s = 51.4m before it stops
Hope this helps ^_^
F = ma where F = 350N, m = 90 so a = -3.89m/s/s
v = u + at so we are trying to find t when v = 0. Since u = 20m/s and a = -3.89,
t = 5.14 seconds
s = ut + .5at^2 so we know that u = 20m/s, a = -3.89m/s/s and t = 5.14s
therefore,
s = 20*5.14 + .5*-3.89*5.14^2
This gives s = 51.4m before it stops
Hope this helps ^_^