Power Rating of a Resistor. The power rating of a resistor is the maximum power the resistor can .safely dissipate without too great a rise in temperature and hence damage to the resistor, (a) If the power rating of a 15-k Ω resistor is 5.0 W, what is the maximum allowable potential difference across the terminals of the resistor? (b) A 9.0-kΩ resistor is to be connected across a 120-V potential difference. What power rating is required? (c) A 100.0-Ω and a 150.0-Ω resistor, both rated at 2.00 W, are connected in series across a variable potential difference. What is the greatest this potential difference can be without overheating either resistor, and what is the rate of heat generated in each resistor under these conditions?
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