The voltage of the generator is 110 V. Forty lamps of 200 Ohm each are connected

The voltage of the generator is 110 V. Forty lamps of 200 Ohm each are connected in parallel to the network. Determine the EMF of the generator if its internal resistance is 0.2 Ohm.

We start solving the problem with a short note given:

U = 110 B;

n = 40;

R = 200 Ohm;

r = 0.2 ohm.

Need to find:

E =?

Since we know from the condition that a parallel connection of 40 lamas is connected to the network, we find the voltage R0 by dividing the total voltage by the number of lamps:

Ro = R / n = 200 Ohm / 40 = 5 Ohm.

We find the current strength as:

I = U / Ro = 110/5 = 22 A.

The E. D. S. of the generator is calculated by the formula:

E = U + I * r.

We know all the meanings. So we substitute them into the formula and do the calculations:

E = 110 + 22 * 0.2 = 114.4 B.