How do I solve this Physics question? Help Please!

Question

Spiderman, whose mass is 78.0 kg, is dangling on the free end of a 11.8-m-long rope, the other end of which is fixed to a tree limb above. By repeatedly bending at the waist, he is able to get the rope in motion, eventually getting it to swing enough that he can reach a ledge when the rope makes a θ = 60.8° angle with the vertical.

How much work was done by the gravitational force on Spiderman in this maneuver?

 ______kJ

Answer 1

Spiderman's final position is higher than his initial position by

Δ h = ( 1 - cos( 60.8) ) 11.8 = 6,04 m

Thus the work done by gravity is - 6.04 (9.81 ) 78.0 = - 4622 J oe - 4.622 kJ