Electronics questions (power handling of resistors in series and parallel)

Hmm, something has changed and I actually won't have this exact number of resistors. All I'm going to have is 5 x 10 Ohm jobbies.

All rated at 100W, how much power can I squirt into this load?

Because they're all identical, I seem to remember that a chain of N resistors each rated for P watts can dissipate NP watts. So 500 watts?


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I would be carefull making a load like that. At RF, the resistors aren't purely resistive but have parasitics, so inductance and capacitance comes into play making your load impedance vary. It will be better if you find resistors that you can use in parallel but it's very dependant on frequency. The lower the frequency the more tolerant to parasitics it is but at high frequencies you may not get away with it.
 
@Bear Yes, I know that. The resistors I'm using are specifically non inductive but I appreciate that the higher in frequency I go, the things will vary. Five resistors in series is (for example) a good chunk of a wavelength at 23cms. It's largely going to be used for HF anyway or maybe up to 144MHz at a push. Once it's all built, I'll do a full sweep to see what the impedance is.
 
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