What is the Relationship Between Spring Stretching Distance and Applied Work?

[firezap]

Homework Statement

See image attachment

Homework Equations

Fs = kx
Es = 1/2 kx^2
ET1 = ET2 which is Eg1 + Ek1 + Es1 + work applied = Eg2 + Ek2 + Es2 + friction

The Attempt at a Solution

grade 12. Please help i never did anything like this.

 

[Doc Al]

This is a force/equilibrium problem, not an energy problem.

A hint to start you off: If you look at diagram I and imagine the spring cut into three pieces, how much does each piece stretch?

 

[firezap]

each piece will stretch 1 cm

 

[Doc Al]

each piece will stretch 1 cm

Good. So now you know that the weight of the complete rod will stretch one of the spring pieces by 1 cm. How much will the weight of 1/3 of the rod stretch one of those spring pieces?

Use this reasoning to figure out how much each spring stretches in diagram II.

 

[firezap]

1/3 x 1cm = 1/3cm
is it 1/3cm + 2/3cm + 3/3cm = 2cm

 

[Doc Al]

1/3 x 1cm = 1/3cm
is it 1/3cm + 2/3cm + 3/3cm = 2cm

Good!