Question

An electric iron of resistance 20 ohms takes a current 5a.Calculate the heat developed in 30seconds

Answer 1

Answer:

Explanation: The heat developed in 30 sec is 15 kj or 15000 j.

Answer 2

Answer:

Given resistance R = 20 ohm

Current 1=SA & time t = 30 sec

We know that

heat =

${current}^{2} \times resistannce \times time \\ {h}^{2} \times r \times t \\ now \: put \: the \: give \: value \: we \: get \: \\ h = {5}^{2} \times 20 \times 30 = 25 \times 600 \\ = 15000 \: joule$