# Lesson Worksheet: Elastic Potential Energy and Conservation of Energy Mathematics

In this worksheet, we will practice solving problems that include elastic strings and springs by using the work–energy principle and the conservation of energy principle.

**Q1: **

A particle of mass 3 kg is attached to end of a light elastic spring of natural length 0.5 m and modulus of elasticity 41 N. The spring rests on a smooth horizontal plane with end fixed. The particle is held at rest and then released. Find the initial acceleration of the particle if initially. Take .

**Q3: **

A bowl of mass hangs in equilibrium from the ceiling by a light elastic spring of natural length 0.8 m and modulus of elasticity 7 N. Taking , find the distance the bowl moves when a mass of 1 kg is gently placed in it.

- A m
- B m
- C m
- D m
- E m

**Q4: **

A long spring is formed by joining a light spring of natural length 3.9 m and modulus of elasticity 18.2 N to another light spring of natural length 2.8 m and modulus of elasticity 19.6 N. Find the tension in the combined spring when it is stretched to a length of 8.5 m.

**Q5: **

A ball of mass 0.6 kg hangs in equilibrium from a light spring of natural length 2.5 m and modulus of elasticity 9 N. The ball is then pulled vertically downward and released from rest at a point 0.8 m below its equilibrium position. Taking , find the acceleration the ball experiences immediately after being released.

**Q6: **

On a smooth horizontal surface, a light elastic string of natural length 1.2 m and modulus of elasticity 9 N is fixed at a point on that surface. At its other end, a ball of mass 2.7 kg is attached. If the ball was held at point and then projected horizontally with a speed of 2.2 m/s, how far does it travel before coming to an instantaneous rest?

**Q7: **

One end of a light elastic spring of natural length
3.5 m and modulus of elasticity
24.5 N is attached to a fixed point, ,
whereas the other end is attached to a particle of mass 1.9 kg. The particle is held at a point , which is 2.2 m vertically below . What distance does the particle fall before it comes to rest if it is projected vertically downward from with a speed of 0.7 m/s? Consider the acceleration due to gravity to be 9.8 m/s^{2}, and give your answer correct to two decimal places.

**Q8: **

A particle of mass 3.7 kg is attached to one end of a light elastic string of natural length 1.7 m and modulus of elasticity 291.1 N. The other end of the string is attached to a fixed point . Taking , find the maximum speed of the particle when it is released from rest at . Round the answer to two decimal places.

**Q9: **

One end of a light elastic spring of natural length 1.6 m and modulus of elasticity 14 N is fixed to a point on top of a table. A ball of mass 2 kg is attached to the other end of the spring. The ball is held 0.7 m above so that the spring is vertical and then released. Taking , find the magnitude and direction of the acceleration the ball experiences immediately after being released. Give the magnitude in meters per second squared correct to two decimal places.

- A4.94 m/s
^{2}, downward - B13.74 m/s
^{2}, upward - C2.94 m/s
^{2}, upward - D6.74 m/s
^{2}, downward - E5.86 m/s
^{2}, downward

**Q10: **

A ball, with center and mass , is attached to one end of a light elastic string of natural length and modulus of elasticity , where is the acceleration due to gravity. The other end of the string is fixed at a point on top of a rough horizontal surface. The ball was placed on the surface so that the string was stretched to a length of . Given that the ball remains at rest at this point and is in limiting equilibrium, determine the coefficient of friction between the ball and the surface. The ball is now moved such that the string is stretched to a length of , and then released from rest. Find the total distance, , that the ball will travel before coming to rest.

- A,
- B,
- C,
- D,
- E,