Define power and give its unit. If a solar panel delivers 150 W of power for 3 hours, how much energy does it produce?

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Multiple Choice

Define power and give its unit. If a solar panel delivers 150 W of power for 3 hours, how much energy does it produce?

Power is the rate at which energy is transferred or work is done, measured in watts. One watt equals one joule per second. To find the energy produced, multiply power by time: E = P × t. Here, the panel delivers 150 W for 3 hours. In watt-hours, that’s 150 × 3 = 450 Wh. To express energy in joules, convert hours to seconds: 3 hours = 10,800 seconds. Then E = 150 × 10,800 = 1,620,000 J. So the energy produced is 1,620,000 joules. (Equivalently, 450 Wh equals 1,620,000 J, since 1 Wh = 3600 J.)

Power is the rate at which energy is transferred or work is done, measured in watts. One watt equals one joule per second. To find the energy produced, multiply power by time: E = P × t.

Here, the panel delivers 150 W for 3 hours. In watt-hours, that’s 150 × 3 = 450 Wh. To express energy in joules, convert hours to seconds: 3 hours = 10,800 seconds. Then E = 150 × 10,800 = 1,620,000 J. So the energy produced is 1,620,000 joules. (Equivalently, 450 Wh equals 1,620,000 J, since 1 Wh = 3600 J.)

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