Question

An electric iron 25ohm takes 7A .calculate the heat developed in 0.5 minute​

Answer 1

Explanation:

heat=i²rt

=25×49×0.5/1000

=0.6125 J

Answer 2

Given: Resistance of the iron(R) = 25Ω

Current (I) = 7A

Time taken(t) = 0.5 minute

To Find: Heat developed

Solution:

When current is passed through a conductor with resistance, heat is generated in it.

The heat generated is given as

H = I²Rt, where H is the heat generated, I is the current flowing through the conductor, R is the resistance of the conductor, t is the time for which the current flows

1 minute consists of 60 seconds

Time taken in seconds = Time taken in minutes x 60

Time taken in seconds = 0.5 x 60

                                       = 30 seconds

H = (7)²(25)(30)

   = 49 x 25 x 30

   = 36750 Joule

Therefore, the heat generated in the iron is 36750 Joule.