Question

For a resistor in a direct current circuit that does not vary its resistance, the power that a resistor must dissipate is directly proportional ti the square of the voltage across the resistor. The resistor must dissipate 1/16 watt of power when the voltage across the resistor is 14 volts. Find the power that the resistor must dissipate when the voltage across it is 42 volts.

Answer 1

THe problem is basically telling us:
`P=kV^2`

where P is the power disappated and V^2 is our voltage squared.

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So, for the second example to find the power we simply have to plug k and our voltage back in, so:
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