The diagram below in Fig., shows the arrangement of five different resistances connected to a battery of e.m.f. 1.8 V. Calculate:
a. The total resistance of the circuit
b. The reading of ammeter A.
The diagram below in Fig., shows the arrangement of five different resistances connected to a battery of e.m.f. 1.8 V. Calculate:
a. The total resistance of the circuit
b. The reading of ammeter A.

(a)According to the question, in the diagram given

Let us consider that RXY be the resistance between X and Y

Therefore, 1 / RXY = 1 / 10 + 1 / 40

1 / RXY = 5 / 40 ohm

This implies RXY = 8 ohm

Let us consider that the net resistance between points A and B be RAB

Thus, 1 / RAB = 10 ohm

Hence, the total resistance of the circuit = 18 ohm

(b) Current I = Voltage / Total resistance

I = 1.8 / 18 A

I = 0.1 A

thus, ammeter reading is 0.1 A