Force and pressure on a window?

Question

In a 47 s interval, 569 hailstones strike a glass window of area 0.624 m^2 at an angle 20 degrees to the window surface. Each hailstone has a mass 3 g and a speed 10.8 m/s.
A. If the collisions are elastic, find the average force on the window. Answer in units of N.
B. Find the pressure on the window. Answer in units of N/m^2.

Answer 1

For each hailstone, we only care about the change in momentum in the dimension normal to (that is, perpendicular to) the window. The perpendicular velocity is

vn = ( 10.8 m / s ) sin 20 degrees.

Since the collisions are elastic, the hailstones rebound with the same magnitude of velocity. thus the change in the normal component of the momentum for each hailstone is

2 m vn

Now, Newton's Second Law can be written (and in fact this was Newton's original form) as

F = Δp /Δt = change in momentum / change in time

You now know the change in momentum per hailstone; multiply by the number of hailstones and divide by the elapsed time to get the force. Then the pressure on the window is = force divided by area:

P = F / A

Answer 2

________________________________________--

Time = t = 47 s

number of hailstones = 569

area of glass window = A = 0.624 m^2

angle O = 20 degrees to the window surface
mass of hailstone =m= 3 g =0.003 kg

speed = v =10.8 m/s.

momentum perpendicular to window surface = mvsinO

momentum perpendicular to window surface=0.003*10.8*sin20

momentum perpendicular to window surface=0.011081 kgm/s

As hailstone collides the window elastically

change in momentum of one hailstone=2mvsinO=2*0.011081=0.022162 kgm/s

change in momentum of N hailstone=N2mvsinO

change in momentum of N hailstone=569*0.022162 kgm/s

change in momentum of 569 hailstone =6.30534 kgm/s

change in momentum of window =change in momentum of 569 hailstone =6.30534 kgm/s

Average force on the window= change in momentum of window /time

Average force on the window=6.30534 /47=0.13416 N

A. If the collisions are elastic, find the average force on the window is 0.13416 N
___________________________
B Pressure= P = force / area =0.13416 / 0.624=0.21499 Pa

the pressure on the window is 0.21499 Pa
________________________

Answer 3

To calculate the rigidity you will desire to comprehend what a million atm is in Pascals.... take a million atm = a hundred kPa rigidity distinction = 0.11 atm = 11 kPa rigidity = rigidity / area rigidity = rigidity . area = 11000 . a million.25^2 = 17200 N ( such as the gravity rigidity on 1720 kg a million.7 tonnes ! )