Question

an electric iron of 30Ω takes a current of 5A. calculate the heat developed in 30 seconds​

Answer 1

Explanation:

H=I2Rt

=5×5×30×30

=22500J

Answer 2

Answer:

22500 j

Explanation:

Given:

Resistance (R)  = 30Ω

Current (I) = 5A

Time (t) = 30 seconds

Potential difference (V) = ?

Heat = ?

Now, by ohm's law

V= IR

 =30×5

=150 v

Now,

Heat = VIt

       = 150×5×30

       = 22500 j

Or,

Heat = I^2Rt

       = 5^2×30×30

      = 25×900

      = 22500 j