Answer:
(i) Half
(ii) 3 V
(iii) V₁
Step-by-step explanation:
(i) The given parameters are;
The circuits have identical resistances
The number of resistors in circuit 1 = 1 resistor
The number of resistors in circuit 2 = 2 resistors
Let 'R' represent the value of each resistor, we have;
The total resistance of circuit 1 = R Ohm
The total resistance of circuit 3 = 2·R Ohm
∴ The total resistance of circuit 1 = (1/2) × The total resistance of circuit 3
∴ The resistance of circuit 1 is half the resistance of circuit 3
(ii) The potential difference of each cell, V = 1.5 volts
The number of cells in circuit 2 = 2 cells
The total potential difference of the cells of circuit 2 = 2 × 1.5 volts = 3 × volts = 3 V.
The voltmeter reading = The potential difference across the cell or cells it is applied
∴ The voltmeter reading on voltmeter, V₂, applied across the cells of circuit 2 = 3 V
(iii) The voltmeter reading V₁ = 1.5 V
The voltmeter reading V₂ = 3 V
The voltmeter reading V₃ = 4.5/(2·R) × R = 2.25 V
Therefore, the voltmeter reading with the smallest volt, is V₁ = 1.5 V