Calculating Power Absorbed by a Heater

[songoku]

Homework Statement

A heater rated at 2000 W operating at 250 V is used on a supply of 230 V. If the resistance of the heater is independent of temperature, calculate the power absorbed by the heater.

Homework Equations

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

The Attempt at a Solution

resistance of heater :

$$R=\frac{V^2}{P}=31.25~ \Omega$$

The power absorbed :

$$P'=\frac{230^2}{31.25}=1692.8 ~W$$

Do I get it right?

Thanks

 

[mgb_phys]

Yes,
You don't need to actually work out the resistance, you know power is the ratio of the voltage^2
= 2000*(230^2/250^2)

ps. careful about how many significant figures

 

[songoku]

Hi mgb_phys

Ok, thanks a lot !