A 5 V battery is connected to two 20 Ω resistors which are joined together in series.
(a) Draw a circuit diagram to represent this. Add an arrow to indicate the direction of conventional current flow in the circuit.
(b) What is the effective resistance of the two resistors?
(c) Calculate the current that flows from the battery.
(d) What is the p.d. across each resistor?
A
(b) Since two resistors of 20 ohm are connected in series, the effective resistance will be
R= R1 +R2
Here, R1 = 20 ohm
R2 = 20 ohm
Therefore the effective resistance of the two resistors = 20+20 =40 ohm
(c) Current flowing through the circuit = I = V/R = 5/40 = 0.125 amps
(d) p.d. across each resistance = I x R = 0.125 x 20 = 2.5 V
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