Answer
The magnitude of the average force on the wall from the stream of pellets is $~~10~N$
Work Step by Step
In part (a), we found that the magnitude of the momentum of each pellet is $~~1.0~kg~m/s$
The pellet gun fires ten pellets per second.
We can find the magnitude of the impulse on the stream of pellets from the wall each second:
$J = (10)(1.0~kg~m/s)$
$J = 10~kg~m/s$
By Newton's Third Law, the magnitude of the impulse on the wall from the stream of pellets is equal in magnitude, but opposite in direction, to the magnitude of the impulse on the stream of pellets from the wall.
We can find the magnitude of the average force on the wall from the stream of pellets:
$F~t = J$
$F = \frac{J}{t}$
$F = \frac{10~kg~m/s}{1.0~s}$
$F = 10~N$
The magnitude of the average force on the wall from the stream of pellets is $~~10~N$.
