Spring energy
A spring has a spring constant of 200 N m⁻¹. It is compressed by 0.120 m and used to launch a 0.300 kg block along a horizontal frictionless surface. Calculate the speed of the block as it leaves the spring.
Worked answer
Solution
- Step 1
Elastic potential energy:
Eₛ = 1/2 kx². - Step 2
Eₛ = 1/2 × 200 × 0.120² = 1.44 J. - Step 3
Apply energy conservation:
1.44 = 1/2 × 0.300 × v². - Step 4
v = 3.10 m s⁻¹.
Final answer
3.10 m s⁻¹
Common mistake
Forgetting the factor of one-half in the elastic potential energy equation.
Concepts tested
- elastic potential energy
- kinetic energy
- conservation of energy
Was this explanation helpful?
Next step