Answer:
D = 43 m
Explanation:
given,
initial velocity = 18 m/s
angle θ = 60°
total horizontal distance covered by the shell is

applying conservation of momentum in horizontal direction
m v₀ cos θ = m₁v₁ + m₂ v₂
m v₀ cos θ = 0.5 m v₂
v₂ = 2 v₀ cos θ.
distance covered by the shell from point of explosion
R' = v t
= 
=
= 
= R
total distance traveled by the shell is
D = 
= 1.5 R
= 
D = 
= 42.9 ≅ 43 m
D = 43 m
Mike enters a revolving door that is not moving. Mike should
push at the edge of the door where it is largest distance from the pivot point
in order to produce a torque with the least amount of force. Torque is equal to
t = force x distance.