Question

How much heat will an instrument of 12 watt produce in 1 minute if it is connected to a battery of 12 voltage?

Answer 1

$heat = ( {i}^{2} )rt = v \times i \times t$
$p = v \times i$
$so \: heat = p \times t$
p×t=12×60=720Joules

Answer 2

Given that

P=12W

t=1min=60sec

V=12v

H=?

We know that H=VIT

and power =VI

Then H=Power×time

=12×60

=720Joule