Question

resistance of a 230 volt heating device is 460 ohm. calculate the heat energy produced by it in 10 minutes​

Answer 1

Given:

Resistance of a 230 volt heating device is 460 ohm.

To find:

Heat energy produced by the device in 10 minutes.

Calculation:

The power delivered by the device be P ;

$\sf{ \therefore \: P = \dfrac{ {(voltage)}^{2} }{resistance} }$

$\sf{ = > \: P = \dfrac{ {(230)}^{2} }{460} }$

$\sf{ = > \: P = \dfrac{ 230 \times 230}{460} }$

$\sf{ = > \: P = \dfrac{ 230 }{2} }$

$\sf{ = > \: P = 115 \: watt}$

Now , let heat produced be H ;

$\sf{ \therefore \: H = power \times time}$

$\sf{ = > \: H = 115 \times (10 \times 60)}$

$\sf{ = > \: H = 115 \times 600}$

$\sf{ = > \: H = 69000 \: joule}$

$\sf{ = > \: H = 69 \: kilojoule}$

So, amount of heat produced is 69 kJ.