A force of 23.1 N acts on a 10.0-kg mass in the positive x-direction, while another force of 10.7 N acts in the negative x-direction. The mass is initially at rest.
(a) Find the time rate of change of momentum.
(b) Find the overall change in momentum after 1.85 s.
(c) Find the velocity of the mass at the end of 1.85 s.
(a) Find the time rate of change of momentum.
(b) Find the overall change in momentum after 1.85 s.
(c) Find the velocity of the mass at the end of 1.85 s.
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the net force acting on the object is 23.1N - 10.7N = 12.4N along the plus x axis
force = time rate of change of momentum, so this is 12.4N in the + x direction
F = delta(momentum)/delta t => F delta t = delta (momentum)
where delta(momentum) =change in momentun and delta t = time elapsed
after 1.85s, the momentum has changed by 12.4N x 1.85s = 22.9kgm/s
this is the change in momentum; since the object started from rest, it also represents the final value of momentum, so that the velocity at t=1.85 s is:
v = 22.9kgm/s / 10kg = 2.29 m/s
force = time rate of change of momentum, so this is 12.4N in the + x direction
F = delta(momentum)/delta t => F delta t = delta (momentum)
where delta(momentum) =change in momentun and delta t = time elapsed
after 1.85s, the momentum has changed by 12.4N x 1.85s = 22.9kgm/s
this is the change in momentum; since the object started from rest, it also represents the final value of momentum, so that the velocity at t=1.85 s is:
v = 22.9kgm/s / 10kg = 2.29 m/s