Springs

Any object that deforms elastically (returns to its original shape) obeys Hooke’s Law: (force and extension are directly proportional)

Force (N) = spring constant (N/m) x extension (m)

F=ke

Practical:

1. Add masses onto spring to change force (e.g. 100g = 1N).

2. Measure extension with ruler at each weight, plot F against e.

3. Gradient of graph = spring constant.

4. Avoid systematic error by lining up 0cm with bottom of spring.

5. Avoid parallax error by getting on eye level when measuring.

Straight line through origin: directly proportional relationship

Elastic potential energy:

E=1/2ke²

If spring fires an object, EPE=KE