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. (b) A 9.0-kΩ resistor is to be connected across a 120-V potential difference. What power rating is required?

Video transcript

Hey everyone. So today we're dealing with the problem about resistors and power ratings. So being told that in a system for resistors to operate at 110V and provides a resistance of of, let's highlight this of 10 kg. Then what is the power rating of the resistor? So we can use the formula for power power in watts. And we can recall that one such equivalent is that v squared voltage divided by our resistance. And OEMs is equal to the power of a specific resistor. So we know that our voltage Voltage is 110V And the resistance is 10 kg. However, we want to convert this to OEMs so that we are in our base units. So to convert this while kilo means 10 to the power of three. So this is just 10 times 10 to the power of three homes, 10,000 OEMs. So putting this back into our equation, we get that. It is V squared over r So 110V squared over 10,000 ohms. Which will give us a final answer Of 1.21 once. So the power rating of a 10 kg ohm resistor operating at 110 volts is answer choice. A 100 or 1.21 watts. I hope this helps. And I look forward to seeing you all in the next one