Physics
A resistor of 6 Ω is connected in series with another resistor of 4 Ω. A potential difference of 20 V is applied across the combination. Calculate (a) the current in the circuit and (b) potential difference across the 6 Ω resistor.
Answer
(a) Given,
Two resistors of 6 Ω and 4 Ω are connected in series. If the equivalent resistance of this part is R's then
R's = (6 + 4) Ω = 10 Ω
Potential Difference V = 20 V
Current I = ?
From Ohm's law
V = IR
Substituting the values in the formula above, we get,
20 = I x 10
⇒ I = 20 / 10 = 2 A
Hence, in series, current through the battery = 2 A
(b) Given,
Resistance R = 6 Ω
Potential Difference V = ?
Current I = 2 A
From Ohm's law
V = IR
Substituting the values in the formula above, we get,
V = 2 x 6 = 12 V
Hence, potential difference = 12 V
Related Questions
Five resistors, each of 3 ohm, are connected as shown in figure. Calculate the resistance (a) between the points P and Q, and (b) between the points X and Y.
Two resistors of 4.0 Ω and 6.0 Ω are connected (a) in series, (b) in parallel, with a battery of 6.0 V and negligible internal resistance. For each case draw a circuit diagram and calculate the current through the battery.
Calculate the current flowing through each of the resistors A and B in the circuit shown in figure.
Two resistors of resistance 2 Ω and 3 Ω are connected in parallel to a cell to draw 0.5 A current from the cell.
(a) Draw a labelled diagram of the arrangement.
(b) Calculate the current in each resistor.