In this worksheet, we will practice finding potential energy and the change in it and using it to solve different problems.

**Q2: **

A crane lifts a body of mass 132 kg to a height of 20 m. Find the increase in the bodyโs gravitational potential energy. Consider the acceleration due to gravity .

**Q3: **

A body of mass 543 g is at a height of 22 m above the surface of the ground. Determine its gravitational potential energy relative to the ground, rounding your answer to two decimal places. Take .

- A 58.54 J
- B 117,070.80 J
- C 58,535.40 J
- D 117.07 J

**Q4: **

A body of mass 7.5 kg is at a height of 14 cm above the ground. Determine the potential energy of the body relative to the ground, take .

- A ergs
- B ergs
- C ergs
- D ergs

**Q5: **

A man of mass 92 kg is going from the sixth floor to the tenth floor in a lift. Given that
the height of each floor is 3.3 m, determine the gain in gravitational potential energy.
Consider the acceleration due to gravity to be 9.8 m/s^{2}.

**Q6: **

A helicopter of mass 2,630 kg descended vertically from a height of 250 m to a height of 150 m. Find its loss in gravitational potential energy. Consider the acceleration due to gravity to be and give your answer in Scientific Notation .

- A J
- B J
- C J
- D J

**Q7: **

A body of mass 7 kg moved 52 cm up the line of greatest slope of a smooth plane inclined at to the horizontal. Find the increase in its gravitational potential energy. Take .

- A 3,089.29 joules
- B 35.67 joules
- C 3,567.2 joules
- D 30.89 joules

**Q8: **

A body of mass 8 kg moved 238 cm up the line of greatest slope of a smooth plane inclined at to the horizontal. Calculate the increase in its gravitational potential energy. Take .

**Q9: **

A person of mass 105 kg was hiking up a hill which was inclined to the horizontal at an angle whose sine is . Given that he covered a distance of 87 m, find the change in his gravitational potential energy. Take .

**Q10: **

A ball of mass 317 g was projected vertically upwards at 29 m/s from a point . It passed through a point , at 21 m/s, where is vertically above . Neglecting air resistance, use the work-energy principle to find the increase in the ballโs gravitational potential energy as it moved from to .

**Q11: **

A particle is moving from point to point under the action of the conservative force dynes. Determine the change in the particleโs potential energy, given that the displacement is in centimetres.

**Q12: **

A body is moving in a straight line from point to point under the action of the force . Given that the change in the bodyโs potential energy is 2 joules and that the displacement is in metres, determine the value of the constant .

- A
- B6
- C1
- D

**Q13: **

A body is moving under the action of a constant force , where and are two perpendicular unit vectors. At time seconds, where , the bodyโs position vector relative to a fixed point is given by . Determine the change in the bodyโs potential energy in the first 9 seconds.

**Q15: **

A crane lifts a body of mass 101 kg to a height of 6 m. Find the increase in the bodyโs gravitational potential energy. Consider the acceleration due to gravity .

**Q16: **

A particle is moving from point to point under the action of the conservative force dynes. Determine the change in the particleโs potential energy, given that the displacement is in centimetres.

**Q17: **

A body of mass 3 kg moved 120 cm up the line of greatest slope of a smooth plane inclined at to the horizontal. Find the increase in its gravitational potential energy. Take .

- A 1,764 joules
- B 35.28 joules
- C 3,528 joules
- D 17.64 joules

**Q18: **

A body of mass 580 g is at a height of 10 m above the surface of the ground. Determine its gravitational potential energy relative to the ground, rounding your answer to two decimal places. Take .

- A 28.42 J
- B 56,840.00 J
- C 28,420.00 J
- D 56.84 J

**Q19: **

A helicopter of mass 2,550 kg descended vertically from a height of 190 m to a height of 130 m. Find its loss in gravitational potential energy. Consider the acceleration due to gravity to be and give your answer in Scientific Notation .

- A J
- B J
- C J
- D J

**Q20: **

A ball of mass 334 g was projected vertically upwards at 22 m/s from a point . It passed through a point , at 18 m/s, where is vertically above . Neglecting air resistance, use the work-energy principle to find the increase in the ballโs gravitational potential energy as it moved from to .

**Q21: **

A body is moving in a straight line from point to point under the action of the force . Given that the change in the bodyโs potential energy is joules and that the displacement is in metres, determine the value of the constant .

- A11
- B6
- C
- D