Answer: 2.55 joules, -9.81 joules, -12.36 joules
Explanation:
the parameters given from the question are :
mass (m) = 0.20 kg
height above water (h₁) = 1.3m
depth of the well (h₂) = 5m = -5m (the negative sign is there because it is a depth below the surface )
constant value for acceleration due to gravity (g) = 9.8 m/s
- potential energy (PE) before the stone is released = m x g x h₁
PE₁ = 0.20 x 9.8 x 1.3 = 2.55 joules
- potential energy (PE) when it reaches the bottom of the well= m x g x h₂
PE₂ = 0.2 x 9.8 x (-5) = -9.81 joules
- change in potential energy = PE₂ - PE₁
= -9.81 - 2.55 = -12.36 joules