B.I.S. Physics, Grade 10
Electrical Energy
Energy = power x time taken
Energy = voltage x current x time
E=VIt
unit: Joule
Show your work and round to appropriate units!
1. Calculate the energy of a light bulb that uses 40V and 4A of electricity in 4 seconds.
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2. Calculate the energy of a toaster that uses 200V and 10 A of electricity in 20 seconds.
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3. Calculate the energy used by a light bulb of power 75W in 10 seconds.
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4. Calculate the energy used by a washing machine with 20 A and 240 V in 30 seconds.
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5. Calculate the energy used by a car of power 25 000W in 2 minutes.
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