Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
NEETPhysicsCurrent Electricity

Six identical resistors, each of resistance R , are connected in series to a battery of emf E and internal resistance r = R . The steady current drawn from the battery is I_s . When these six resistors are connected in parallel to the same battery, the current drawn becomes I_p . The ratio I_p I_s is:

Options

  1. A6
  2. B36
  3. C1 6
  4. D7

Correct answer

A. 6

Step-by-step solution

When the 6 resistors are connected in series, their equivalent external resistance is R_s = 6R . The total resistance of the circuit is R_s + r = 6R + R = 7R . The current drawn in series is I_s = E 7R . When the 6 resistors are connected in parallel, their equivalent external resistance is R_p = R 6 . The total resistance of the circuit is R_p + r = R 6 + R = 7R 6 . The current drawn in parallel is I_p = E 7R 6 = 6E 7R . The ratio of the currents is: I_p I_s = 6E 7R E 7R = 6 . Answer: 6

Practice Current Electricity on Quantrex Academy →

More from Current Electricity

A potentiometer wire of 400 cm length has a resistance of 20 . It is connected in series with a resistance of 15 and a accumulator of EMF 6 V (negligible internal resistance). The 2026In the following figure current I equal to 2026The range of voltmeter is 10 V and its resistance is 50 . To convert it to a voltmeter of range 15 V , how much resistance is to be added? 2026When a galvanometer is shunted with a 2 resistance, the deflection is reduced to one-fourth. If the galvanometer is further shunted with a 1 resistance, the further reduction in de 2026A galvanometer can be converted into a voltmeter of certain range by connecting a resistance of 990 in series with it. When the resistance of 480 is connected in series, the range 2026A resistance is to be measured using a meter bridge; the student chooses the standard resistance R to be 100 . The student finds the null point at l₁=16 cm. To get the null point n 2026Which of the following statements is FALSE? A. In a balanced Wheatstone bridge, if the cell and the galvanometer are exchanged, the null point is disturbed. B. A rheostat can be us 2026A potentiometer wire has length 4 m and resistance 8 . The resistance that must be connected in series with the wire and the driving battery of e.m.f. 2 V, so as to get a potential 2026 Full Current Electricity list All NEET PYQs