Question

The current passing through an electric kettle has been doubled. The heat produced will become:; A. half; B. double; C. four times; D. one-fourth

Answer 1

Explanation:

h = I^2 * r*t

if I is doubled

h= (2I)^2 *r * t

= 4(I^2 *r*t)

=4h

Ans=c 4 times

Answer 2

Answer:

When the current will be doubled then heat produced will be four times in the kettle.

Explanation:

Consider that H is the heat produced,

while $i$ is the current, $r$ is the resistance and t is the time.

We know the relation:

           $H=i^{2}Rt$

when the current passed  doubled,

Here current becomes $2i$ ,

Then     $H'=(2i)^{2}Rt$

 ∴           $H'=4i^{2}Rt\\ H'=4H$

Therefore the heat generated will be increased by four times.