A resistance of 40 ohms and one of 60 ohms are arranged in series across 220 volt supply. Find the heat in joules produced by this combination of resistances in half a minute.

Question

Philoid · Accepted Answer

Here it is given that R₁ = 40 ohms, R₂ = 60 ohms, V = 220V, t = 30 sec

Here R₁ and R₂ are arranged in series connection.

So the equivalent resistance = R = 40+60 = 100 ohms

According to Ohm's law, we know that

V = IR

I = V/R

I = 220/100 = 2.2amp

As we know that heat produced in joules is given by H = I²Rt

Substituting the values of I, R and t in eq. H = I²RT

H = (2.2)² X 100 X 30

H = 14520 J