A child pushes, with F_{1}, his sister on a swing, generating torque, τ_{1} which causes her to swing forward. If he then gets in a swing that hangs on a chain that is 20% shorter and his sister pushes with a force, F_{2}, that is directed at a 30º angle to the swing, what is the relationship between F_{1} and F_{2} if they generate the same torque?

A) F_{1} = F_{2}

B) 2.5 F_{1} = F_{2}

C) F_{1} = 2.5 F_{2}

D) 2 F_{1} = F_{2}