Question

Q 24 full solution.........

Answer 1

Hi,

Let's get to know the basics first...
If resistors are connected in series, their resistance must be added up.

If they are connected in parallel with other resistors, then the reciprocal of their resistance must be added then it must be inversed to get the total resistance.

So,
$2 + 2 = 4$
And,
$= \frac{1}{4} + \frac{1}{3} \\ = \frac{3}{12} + \frac{4}{12} \\ = \frac{7}{12}$
Now take the reciprocal to get the total resistance,
$\frac{12}{7}$
Therefore, The total resistance of the given circuit is 12/7 Ohms

Now we'll use the formula to find heat or energy,
$h = heat \\ i = current \\ r = resitance \\ t = time\\ \\ h = {i}^{2} \times r \times t$
Let's assume time is 1.
Let's substitute the values to get the energy,
$12 = {i}^{2} \times 3 \times 1 \\ \frac{12}{3} = {i}^{2} \\ i = \sqrt{4} = 2$
Therefore, heat produced in 4Ohm resistor is,
$h = {2}^{2} \times 4 \times 1 \\ h = 4 \times 4 \times 1 \\ h = 16 \: joules$
16 joules is the heat energy liberates.
I think there is some printing error. Or there might be some mistake in my solving if any in my solve please let me know, I'll correct it. Thanks