PART ONE In a 52 s interval, 381 hailstones strike a glass window of area 1.124 m^2 at an angle 43◦ to the window surface. Each hailstone has a mass of 5 g and speed of 6 m/s. If the collisions are elastic, find the average force on the window.
Answer in units of N.

PART TWO
Find the pressure on the window. Answer in units of N/m^2.

change in momentum is (delta,p))= 2*m*v*sin(23) ,parallel velocity to the window remains unchanged  ignore, perpendicular velocity changes by twice the initial  perpendicular velocity as the hail stone changes direction with respect to the  perpendicular .  force=total(delta,p)/t

hence force=450*2*m*v*sin(23) /46, pressure =force/area=450*2*m*v*sin(23) /46*1.187

This is not fluid mechanics,

Just think about splitting the velocity in to vector components use elastic collision fact is energy is same after collision hence so is the speed ,use known equations.

Explanation: