Question

$\large\underline\bold\purple{Question}$
An electric iron of resistence 20 Ω takes a current of 5 A. Calculate the heat developed in 30 s.
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Answer 1

ANSWER:-

We have to find the heat generated from the electric iron - -

To solve these questions, we must know the formula - >

$\huge\red{\underline{{\boxed{\textbf{H = I. r . t}}}}}$

Where,

I = current

r = resistance

t = time

Given,

Electric iron of resistence is (r) = 20Ω

Current flow in electric iron (I) = 5 Ampere

Heat generated in time (t) = 30 seconds

So,

By using given form ( which I taught you above)

We put value there - >

$H = i^2 × r × t \\ \\ = > H = (5)^2 \: \times \: 20 \: \: \times \: \: 30 \: \\ \\ = > H \: = 15000 \: joule$

Hence, the heat developed in 30 s is 15000 joule.

Answer 2

Given :

• Electric iron of resistence = 20 Ω
• Current = 5 A
• Time = 30 s

To Find :

Heat produced in 30 s.

Solution :

$\sf\ Here,$

$\sf\ Current, I = 5A$

Resistance, R = 20Ω

$\sf\ Time, t = 30 s$

Concept:

$\sf\ Calculation\:of\:heat\: energy=The\:heat\:energy\:in\: Joules$

$\sf\ can\:be\: calculated\:by\:using\:the\:formula.$

$\dashrightarrow\: \sf\ H = I^2 \times R \times t$

Calculation :

$\sf\ Heat\: Produced, = H=I^2 \times R\times t$

$\dashrightarrow\: \sf\ H =(5)^2 \times 20\times 30$

$\dashrightarrow\: \sf\ H =25 \times 20\times 30$

$\dashrightarrow\: \underline{\boxed{\bf{\red{ H = 15000 J}}}}$

$\sf\ Thus,\:the\:heat\: developed\:is\:15000 Joules$