A cell of emf 1.8 V and internal resistance 2 ohm is connected in series with an ammeter of resistance 0.7 ohm and resistance of 4.5 ohm as shown in figure.
(a) What would be the reading of the ammeter?
(b) What is the potential difference across the terminals of the cell?
According to the question,
(a) ε = 1.8 V
Total resistance = 2 + 4.5 + 0.7
= 7.2 W
I =?
I = ε / R
I = 1.8 / 7.2
I = 0.25 A
(b) I = 0.25 A [calculated in (a) part]
internal resistance total resistance = 4.5 + 0.7
= 5.2 ohm
V = IR
V = 0.25 × 5.2
Hence,
V = 1.3 V
