BB Gun Scene

The Physics Behind The BB Gun Shooting Scene: Home Alone 1

In case you've forgotten the scene...

Here...
Harry is seen getting shot in the groin within a very short distance with a BB gun. 

What we can assume...
In this scene, Kevin's gunshot is an example of projectile motion when he shoots Harry in the groin at an approximate angle of 60 degrees, only 0.02 metres away, within 0.25 seconds (0.08m/s). With these givens, we can find the height at which Kevin was shooting at. 

Finding the height of the gun...
x stuff:
△dx = 0.02m
vx = 0.08Cos60 = 0.04m/s
t = 0.25s

y stuff:
vy1 = 0.08Sin60 = 0.07m/s
a = -9.8 m/s^2
t = 0.25s
△dy = ?
vy2 = ?

△d = v1t + 1/2at^2
      = (0.07) (0.25) + (-4.9) (0.25)^2
      = -0.28875
∴ h = 0.29m

Finding impact velocity...
Vimpac = √(0.04)^2 +(0.07)^2
             = √0.0065
             = 0.08

v2y = v1 + at
       = 0.07 + (-9.8)(0.25)
       = -2.38m/s

Ø = tan -1(0.07/0.04)
    = 60 degrees.

∴ the impact velocity was 0,08 m/s (60 degrees above horizon)

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