Question

(a) Write down the formula for the heat produced when a current I is passed through a resistor R for time t.
(b) An electric iron of resistance 20 ohms draws a current of 5 amperes. Calculate the heat produced in 30 seconds.

Answer 1

Answer:

(a) H = I²Rt

(b) H = 15000 Joules

Explanation:

(a) H = I²Rt

H = Heat Produced

I = Current

R = Resistance

t = time

(b) Given:-

Resistance(R) = 20 ohm

I = 5 Ampere

t = 30 seconds

H = I²Rt

H = 5² x 20 x 30

H = 15000 Joules

Answer 2

Given:

Resistance $(R) = 20 \Omega$

Current $(I) = 5A$

Time $(t) = 30sec$

To find:

(A) Formula for the heat produced in a wire

(B) Heat produced in a wire

Solution:

(A)

When a current $(I)$  is passed through a resistor $(R)$ for time $(t)$ then heat$(H)$ produced in wire is given by

                                 $H = I^2Rt$

(B)

We know that heat produced in a wire is given by below formula

                  $H = I^2 Rt$

Putting the values of Current, Resistance and time

                             $H = 5^2 \times 20 \times 30$

                            $H = 15000J$

Thus, Heat produced in wire is $15000J$