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Ed asked in Science & MathematicsPhysics · 1 decade ago

Find the cost of electrical energy used by a lamp in 3.5hours if energy costs 17p/kWh and it uses 250W in 0.5h?

I think you need to use these formulas:

E = P x T

Cost = kWh x cost per kWh

1 Answer

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  • Anonymous
    1 decade ago
    Favorite Answer

    If the lamp uses 250W in 0.5 hours, it uses 500W/hr = 0.5 Kw/hr

    If the cost is 17p/kWh, your cost will be 17 x 3.5 x 0.5 = 29.75p

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