Answer:
Em₀ = 245 J
Explanation:
We can solve this problem with the concepts of energy conservation, we assume that there is no friction with the air.
Initial energy the highest point
Em₀ = U
Em₀ = m g h
The height can be found with trigonometry
The length of the pendulum is L and the length for the angle of 60 ° is L ’, therefore the height from the lowest point is
h = L - L’
cos θ = L ’/ L
L ’= L cos θ
h = L (1 - cos θ)
We replace
Em₀ = m g L (1- cos θ)
Let's calculate
Em₀ = 10 9.8 5.0 (1 - cos 60)
Em₀ = 245 J
Well plants breathe carbon and let out oxygen so it cleans the air, not sure about the energy use...
