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7nadin3 [17]
2 years ago
13

Why are electromagnets more useful than permanent magnets in many

Physics
2 answers:
Likurg_2 [28]2 years ago
5 0

Answer: Electromagnets can be turned on and off by controlling the current

Explanation:

Tasya [4]2 years ago
5 0

B. By controlling the current, electromagnets can be turned on and off

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How long does it take for a 3.5 kW electric water heater to heat 40 kg of water? from 20 ° C to 75 ° C? The specific heat capaci
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2633.7 s

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P = cm(t₂-t₁)/t.................. Equation 1

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make t the subject of the equation

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