A mass of 100g strikes the wall with speed 5m/s at an angle of 60 and rebounds with the same speed. If the contact time is 2*10^-3 sec., what is the force applied by the wall?

Answer 1

Let θ=60º be the angle that the velocity makes with the wall.
Δp(x)= p2(x)-p1(x)= m•v(x) – (-m•v(x)) =2m•v(x)= 2m•v•sin θ
Δp(y)= p2(y)-p1(y)=0
F•Δt=Δ p(x)= 2m• v•sin θ
F=2m• v•sin θ/Δt