Practice Power And Energy In Electricity (1.5)

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9 questions

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6 sample questions

Question 1.
What is the formula for electric power?
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Think about the relationship between voltage and current.
Question 2.
How is electrical energy calculated?
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Recall that energy is power multiplied by time.
3Question 3.
What is the formula to calculate electric power?
- P = I + V
- P = V × I
- P = I / V
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Think about how power relates to voltage and current.
4Question 4.
True or False: Electrical energy is measured in joules and kilowatt-hours.
- True
- False
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Consider how we typically measure energy in households.
Question 5.
You have a device rated at 1500 W. If it is run for 3 hours, how much energy is consumed in kilowatt-hours?
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Convert watt-hours to kilowatt-hours at the end.
Question 6.
A heating element has a resistance of 20 Ω and is connected to a 120 V supply. Calculate the power dissipated and the current flowing through the element.
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Find current first using resistance, then use that to find power.

5 more questions in this section. Enroll free to practise them all.