Question

The resistance of 100 W bulb is less than resistance of 40 W bulb. Explain the reason.

Answer 1

Ok so we know that electric power is:

$P=UI=I^2R$

If we express resistance.

$R=\dfrac{P}{I^2}$

Now if you have 100W of power you will probably get a bigger resistance than with 40W of power.

However here it says that the resistance of 40W bulb is bigger than 100W bulb. Which means the statement is incorrect.

Hope this helps.

r3t40