- The mechanism for releasing the ball on a pinball machine contains a light elastic spring of natural length 15 cm and modulus of elasticity \(\lambda\).
The spring is held compressed to a length of 9 cm by a force of 4.5 N .
- Find \(\lambda\).
- Find the work done in compressing the spring from a length of 9 cm to a length of 5 cm .
(4 marks)