Question

If a 2-kg block compresses a spring 800mm from its relaxed state, how much potential energy does the block have due to the spring? Assume the spring constant, k = 25 N/m.

Answer 1

8 Joule

Explanation:

Mass of block = 2 kg

Displacement = x = 800 mm = 0.8 m

Spring constant = k = 25 N/m

Potential Energy of a spring

Work done = Difference in Potential Energy

Work Done = Δ P.E.

`\Rightarrow \Delta\ P.E.=(1)/(2)kx^2`

⇒P.E. = 0.5×25×0.8²

⇒P.E. = 8 Nm = 8 Joule

Here already the spring constant and displacement is given so the mass will not be used while calculating the potential energy.