12th Physics 2018 Set1 Delhi Board Paper Solution
A 10 V cell of negligible internal resistance is connected in parallel across a battery of emf 200 V and internal resistance of 38 Ω as shown in the figure. Find the value of the current in circuit.
Since, the positive terminals are connected to the offsite ends of the resistor, they send the current in opposite directions.
Hence, the net emf = 200-10 = 190 V
∴ current in the circuit I = E/R
= 190V / 38 Ω
= 5 A
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