Practice Electrical Energy And Power (2.7) - Current Electricity

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10 questions

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6 sample questions

Question 1.
Calculate the energy used by a 100 W device operating for 1 hour.
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Use W = Pt, where t is 3600 s.
Question 2.
What is the power in watts if 300 joules of energy are consumed in 30 seconds?
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Use P = W/t.
3Question 3.
What is the unit of electrical energy?
- Joule
- Watt
- Volt
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Remember energy and power have different units.
4Question 4.
True or False: 1 kWh is equal to 3.6 million joules.
- True
- False
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Consider how kilowatt is defined.
Question 5.
A factory runs a machine that consumes 1500 W for 24 hours. How much energy does it use in kWh?
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Use Energy = Power x Time and convert to kWh.
Question 6.
If a car's battery supplies 12 V and the total current drawn is 10 A, what is the electrical power used?
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Apply the formula P = VI.

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