More Lessons for IGCSE Physics
A series of free GCSE/IGCSE Physics Notes and Lessons.
Electrical Energy and Power
The following diagram gives the formula for Electrical Energy and Power. Scroll down the page for more examples and solutions on how to use the formula.
Energy Transfer by Appliances
• Describe how different domestic appliances transfer energy.
• Describe what is meant by the power rating of an appliance.
How appliances transfer electrical energy into other forms such as thermal energy or kinetic energy?
What is meant by the power rating for an appliance?
Calculating energy transferred by appliances
1. A kettle has a power rating of 2200 watts and is used for 80 seconds. Calculate the total energy transferred.
2. A fan has a power rating of 20 watts and is used for 1 hour. Calculate the total energy transferred.
3. An iron is used for five minutes and a total of 600,000 joules of energy is transferred. Calculate the power of the iron.
4. A blender has a power of 400 watts and a total of 48,000 joules of energy is transferred when the blender is in use. Calculate the time that the blender is used for.
Rotate to landscape screen format on a mobile phone or small tablet to use the Mathway widget, a free math problem solver that answers your questions with step-by-step explanations.
You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.
We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.