Before starting this problem, review Conceptual Example 3 in your text. Suppose that the hail described there comes straight down at a mass rate of m/?t = 0.030 kg/s and an initial velocity of v0 = -15 m/s and strikes the roof perpendicularly. Suppose that the hail bounces off the roof of the car with a velocity of +15 m/s. Ignoring the weight of the hailstones, calculated the force exerted by the hail on the roof. N

0.9 N

Explanation:

The force exerted on an object is related to its change in momentum by:

where

F is the force exerted

is the change in momentum

is the time interval

The change in momentum can be rewritten as

where

m is the mass

u is the initial velocity

v is the final velocity

So the formula can be rewritten as

In this problem we have:

is the mass rate

is the initial velocity

is the final velocity

Therefore, the force exerted by the hail on the roof is:

correct it is c.) b b