Halliday, Resnick & Walker — Center of Mass and Linear Momentum: Problem 30

Two average forces. A steady stream of 0.250 kg snowballs is shot perpendicularly into a wall at a speed of 4.00 m/s. Each ball sticks to the wall. Figure 9.27 gives the magnitude F of the force on the wall as a function of time t for two of the snowball impacts. Impacts occur with a repetition time interval \(\Delta t_r = 50.0 \text{ ms}\), last a duration time interval \(\Delta t_d = 10 \text{ ms}\), and produce isosceles triangles on the graph, with each impact reaching a force maximum \(F_{max} = 200 \text{ N}\). During each impact, what are the magnitudes of (a) the impulse and (b) the average force on the wall? (c) During a time interval of many impacts, what is the magnitude of the average force on the wall?