Practice Efficiency: The Ratio of Useful Output to Total Input - 3.4 | Module 3: Energy, Work, and Power | IB Board Grade 9 Physics
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3.4 - Efficiency: The Ratio of Useful Output to Total Input

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Learning

Practice Questions

Test your understanding with targeted questions related to the topic.

Question 1

Easy

Define efficiency in your own words.

πŸ’‘ Hint: Think about how effectively something performs its job.

Question 2

Easy

What is waste energy?

πŸ’‘ Hint: Consider what happens to energy that isn't used efficiently.

Practice 4 more questions and get performance evaluation

Interactive Quizzes

Engage in quick quizzes to reinforce what you've learned and check your comprehension.

Question 1

What does efficiency measure?

  • A measure of energy transformation
  • The ratio of useful output to total input
  • The speed of energy transfer

πŸ’‘ Hint: Think about how we define efficiency.

Question 2

True or False: All machines can be 100% efficient.

  • True
  • False

πŸ’‘ Hint: Consider the implications of friction and heat.

Solve 1 more question and get performance evaluation

Challenge Problems

Push your limits with challenges.

Question 1

A factory uses 1,500 kJ of energy and produces 550 kJ of useful work. Calculate its efficiency and discuss ways to improve it.

πŸ’‘ Hint: Think about energy losses in machinery.

Question 2

Analyze the impact of improving the efficiency of a vehicle that currently operates at 20% efficiency to 40%. How would this affect fuel costs and emissions?

πŸ’‘ Hint: Consider the relationship between fuel consumption and emissions.

Challenge and get performance evaluation