Topic: Work Done and Energy Transfer

Part 1 - Keywords:

1. Work done

2. Energy transfer

3. Force

4. Displacement

5. Newton

6. Joule

7. Distance

8. Equation

9. Newton-metre

10. Movement

Part 2 - Key Facts:

• Work Done: When a force causes an object to move through a distance, work is done on the object.

• Energy Transfer: Work done on an object results in a transfer of energy to or from the object.

• Equation for Work Done: The work done by a force on an object can be calculated using the equation:

• work done=force × distance moved along the line of action of the force

  𝑊=𝐹×D

• Units:

  • Work done (W) is measured in joules (J).

  • Force (F) is measured in newtons (N).

  • Distance (D) is measured in metres (m).

• Joule Definition: One joule of work is done when a force of one newton causes a displacement of one metre.

• Energy Conversion: 1 joule (J) is equivalent to 1 newton-metre (N·m).

Part 3 - Quick Quiz:

1. What is the unit of work done?

   a) Newton

   b) Metre

   c) Joule

   Answer: c) Joule

2. Which equation is used to calculate work done?

   a) W = F + D

   b) W = F × D

   c) W = F / D

   Answer: b) W = F × D

3. How much work is done when a force of 2 newtons moves an object 3 metres?

   a) 5 joules

   b) 6 joules

   c) 3 joules

   Answer: b) 6 joules

Part 4 - Going Further: Describe a real-life scenario where work is done on an object, including the forces involved and the distance over which the object is moved. Calculate the work done using the given values.

Answer: Consider a person pushing a shopping trolley with a force of 50 newtons over a distance of 10 metres. The force applied to the trolley is in the same direction as the movement.

Using the equation for work done: 𝑊=𝐹×𝑠

 𝑊=50 N×10 m

 𝑊=500 J

Therefore, 500 joules of work is done on the shopping trolley. This energy transfer results in the trolley being displaced over the given distance.

Part 5 - Revision Tips: Practice calculating work done with different values of force and distance. Draw diagrams to visualise the force applied and the direction of movement to ensure a clear understanding of the concepts.

Part 6 - More Help: