Efficiency and reducing unwanted energy transfers

In this lesson we will be exploring the topic of reducing energy losses. We will consider how this affects the efficiency of a system and use this in calculations.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.Which of these is the correct definition of power?

1/5

Q2.Revision: Which is the correct statement about closed systems?

2/5

Q3.What is the power of a motor that transfers 450 J of energy in 9 s?

3/5

Q4.Revision: A ball dropped from a cliff has 100 J in its GPE store as it is released. What is the value of the KE store when it just reaches the ground?

4/5

Q5.How long would it take a 400 W motor to transfer 2000 J of energy?

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.Which of these is the correct definition of power?

1/5

Q2.Revision: Which is the correct statement about closed systems?

2/5

Q3.What is the power of a motor that transfers 450 J of energy in 9 s?

3/5

Q4.Revision: A ball dropped from a cliff has 100 J in its GPE store as it is released. What is the value of the KE store when it just reaches the ground?

4/5

Q5.How long would it take a 400 W motor to transfer 2000 J of energy?

5/5

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Efficiency and reducing unwanted transfers

This quiz will test your understanding of efficiency and unwanted transfers. Additionally it will test your understanding of earlier lessons within this topic.

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.Revision: Which energy store is increased when an object is heated?

1/6

Q2.Revision: What is the power of a motor that transfers 550 J of energy in 11s?

2/6

Q3.Which of these is a correct equation for percentage efficiency?

3/6

Q4.If a 0.75 efficient motor produces 150 W of useful power, what was the input power?

4/6

Q5.Which of these are ways in which a motor lifting a crate could transfer energy less usefully? (select 4)

Select four (4) boxes

5/6

Q6.Which material will have the lowest thermal conductivity?

6/6

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Efficiency and reducing unwanted transfers

This quiz will test your understanding of efficiency and unwanted transfers. Additionally it will test your understanding of earlier lessons within this topic.

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Q1.Revision: Which energy store is increased when an object is heated?

1/6

Q2.Revision: What is the power of a motor that transfers 550 J of energy in 11s?

2/6

Q3.Which of these is a correct equation for percentage efficiency?

3/6

Q4.If a 0.75 efficient motor produces 150 W of useful power, what was the input power?

4/6

Q5.Which of these are ways in which a motor lifting a crate could transfer energy less usefully? (select 4)

Select four (4) boxes

5/6

Q6.Which material will have the lowest thermal conductivity?

6/6

Lesson summary: Efficiency and reducing unwanted energy transfers

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The next lesson in Energy is "Specific heat capacity"

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