Question

Resistors are assigned a power rating. If the power rating is exceeded significantly, the resistor will overheat and crack. Suppose you have a 11 kΩ, 0.4 watt resistor. What is the maximum voltage it can safely handle (volts)?

Answer 1

Answer:

The Maximun voltage is 66.33 volts.

Explanation:

According to the statement the power rating is 0.4 watt. we have to find a voltage that give us that power so we can set that value as a limit.

according with Ohm's law

$I=\frac{V}{R}$ (1)

and

$P=V.I$ (2)

if we sustitute (1) in (2)

$P= \frac{V^{2}}{R}$

So the voltage that gives a power of 0.4 watt is given by:

$V=\sqrt{P*R} =\sqrt{0.4*11000}$

$V=66.33 Volts$

so 66.33 is the limit, if we apply a voltage greater than 66.33 the resistor will overheat and get destroyed.