Answer:
Explanation:
Here potential energy lost = mgh
h = L ( 1 - cos 46 ) where L is length of rope
= 2.6 x ( 1 - cos 46 )
PE lost = 20 x 9.8 x 2.6 ( 1 - cos 46 )
= 155.6 J
gain of kinetic energy = loss of PE
1/2 m v² = 155.6
.5 x 20 x v² = 155.6
v² = 15.56
v = 3.94 m /s
