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2 years ago

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A 300W hot plate produces 45,000 J of thermal energy while operating for 2 min. What is the efficiency of this devide? it need t

o be 80%, 67% 0.8% or 0.67%

1 answer:

Gekata [30.6K]2 years ago

5 0

Answer:

Explanation: P = 300 W and t = 2 min = 120 s

Energy Q = Pt = 300 W · 120 s = 36 000 J.

Thus, plate can not produce 45 000 J heat.

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Answer:

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Answer:

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