An electric iron of resistance $20 \Omega$ draws a current of $5 \mathrm{~A}$. The heat developed in the iron in 30 seconds is :

Heat developed in the iron is given by $H = I^2 R t = (5)^2 (20) (30) = 15000 ext{ J}$

Question 141 markMCQSection A

$20 \Omega$

Electricity

Electricity

(A)

15000 J

(B)

6000 J

(C)

1500 J

(D)

3000 J

H = I^2 R t = (5)^2 (20) (30) = 15000 ext{ J}

Heat developed

electric iron

resistance

current

time

Hint

$H = I^2 R t$

Quick oral answer

$The heat developed in the iron is 15000 J.$

The heat developed in the iron is directly proportional to the square of the current, the resistance, and the time. Therefore, the heat developed is maximum when the current is maximum, the resistance is maximum, and the time is maximum.

$The heat developed in the iron is directly proportional to the square of the current, the resistance, and the time.$

Q14 of 39 questions

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$This question carries 1 mark in the CBSE Class 10 Science 2024 examination.$

$This question is from the chapter "Electricity" in the CBSE Class 10 Science syllabus.$

$This question covers the topic "Electricity" from CBSE Class 10 Science.$

$This is a MCQ question from Section A in the CBSE Class 10 Science 2024 paper.$