Answer:
The potential energy when it reads 40 N is [tex]PE = 5.33 \ J[/tex]
Explanation:
From the question we are told that
The lowest reading of the spring balance is 0 N and this is at 0 cm = 0 m
The height reading of the spring balance is 60 N and this is at 20 cm = 0.20 m
Generally the length corresponding to the reading of 40 N is mathematically represented as
[tex]d = \frac{40 * 0.20 }{60 }[/tex]
=> [tex]d = 0.133 \ m[/tex]
Generally the potential energy is mathematically represented as
[tex]PE = m * g * d[/tex]
Here
[tex]F = mg = 40 N[/tex]
So
[tex]PE = 40 * 0.133[/tex]
=> [tex]PE = 5.33 \ J[/tex]
