Work-Energy Theorem- Spring Constants and Energy
Obj: Determine the spring constant k of a spring using energy conservation.
Materials: meter stick, jump-up toy (Oriental Trading Co.*), balance

Procedures:
1. Determine the mass of the jump-up toy to 1.0 x 10^-4 kg.
2. Measure to the nearest 1.0 x 10^-3 m the exact distance the spring will compress on the jump-up toy in the locked position.
3. Compress the spring until the toy locks.
4. Estimate the vertical height the toy jumps for five trials. Determine the average.

Analysis (Show all equations, calculations, and units throughout.)
1. From the height (h) the toy jumped, determine the V_y component of velocity.
2. Calculate the increase in gravitational potential energy of the toy at the height h.
3. Using the equations of the Work-Energy Theorem, determine the spring constant k of the toy's spring using the
                            (a) final gravitational potential energy or     (b) initial kinetic energy.
4. Compare your answers for k with others in the class and draw a conclusion about height h and k.
5. How could the toy be manufactured to make it go higher? List at least two ways.
6. How much work did you do compressing the spring, and what final force did you apply (F = kx)?

(*Use of toy does not endorse the Oriental Trading Co.)

---

Back to the Brockport High School Science Department