Wheatstone Bridge Questions for NEET 2027All 31 problems — MCQs, numericals & ReNEET 2026-style reasoning, with worked solutions

✨ Practise all 31 Wheatstone Bridge Questions

Wheatstone Bridge is a high-yield part of Current Electricity. This is the complete set — real NEET PYQs plus ReNEET 2026-style reasoning, each with an instant worked solution.

1. Q1. In the network shown the four arms are P = 3 $\Omega$, Q = 6 $\Omega$, R = 3 $\Omega$, S = 6 $\Omega$ with a 9 $\Omega$ bridge arm, fed by a 9 V battery across A–B. The current from the battery is:
   
   A2 AB1 AC0.5 AD3 A
2. Q2. The bridge is balanced with arms P = 5 $\Omega$, R = 10 $\Omega$ (lower-left) and S = 4 $\Omega$ (lower-right). The upper-right arm Q is:
   
   A2 $\Omega$B12.5 $\Omega$C8 $\Omega$D5 $\Omega$
3. Q3. In the symmetric bridge network shown all five resistors are 2 $\Omega$. The equivalent resistance between A and B is:
   
   A3 $\Omega$B2 $\Omega$C1 $\Omega$D4 $\Omega$
4. Q4. A square ABCD has each side 2 $\Omega$ and one diagonal AC of 2 $\Omega$. The equivalent resistance between A and C is:
   
   A1 $\Omega$B2 $\Omega$C0.8 $\Omega$D4 $\Omega$
5. Q5. In a metre-bridge, an unknown resistance X (left gap) is balanced against R = 30 $\Omega$ (right gap); the balance point is at 40 cm from A. The value of X is:
   
   A45 $\Omega$B60 $\Omega$C20 $\Omega$D75 $\Omega$
6. Q6. A 6 $\Omega$ bridge network has arms 4 $\Omega$, 8 $\Omega$, 4 $\Omega$, 8 $\Omega$ (balanced) across a 12 V source A–B. The current drawn is:
   
   A1 AB0.5 AC4 AD2 A
7. Q7. Each arm of the bridge shown is 2 $\Omega$ and the bridge (galvanometer) arm is 5 $\Omega$. A 4 V battery is connected across A and B. The current drawn from the battery is:
   
   A1 AB2 AC1.6 AD0.5 A
8. Q8. For the bridge shown to be balanced, the arms P = 2 $\Omega$, Q = 3 $\Omega$ and R = 4 $\Omega$. The fourth arm S must be:
   
   A2.67 $\Omega$B8 $\Omega$C6 $\Omega$D2 $\Omega$
9. Q9. In a metre-bridge, R = 10 $\Omega$ is in the left gap and an unknown S in the right gap; the null point is at 25 cm from A. The value of S is:
   
   A3.33 $\Omega$B30 $\Omega$C40 $\Omega$D25 $\Omega$
10. Q10. A Wheatstone bridge is balanced (no galvanometer deflection) with arms P = 4 $\Omega$, Q = 6 $\Omega$, the lower-right arm S = 9 $\Omega$. The lower-left unknown arm X is:
    
    A6 $\Omega$B13.5 $\Omega$C6.75 $\Omega$D9 $\Omega$
11. Q11. In the balanced Wheatstone bridge shown the galvanometer shows no deflection. The arms are P = 10 $\Omega$, Q = 20 $\Omega$ and R = 15 $\Omega$. The value of the unknown resistance S is:
    
    A7.5 $\Omega$B30 $\Omega$C45 $\Omega$D12.5 $\Omega$
12. Q12. A meter bridge is balanced when the null point is at 40 cm from the left end. If a resistance of 15 Ω is connected in the left gap, what is the unknown resistance in the right gap?
    A25 ΩB10 ΩC40 ΩD22.5 Ω
13. Q13. A meter bridge wire of total length 100 cm has a resistance of 9 Ω. An unknown resistance X is connected in the left gap and a standard resistance of 6 Ω is connected in the right gap. The balance point is obtained at 40 cm from the left end. What is the value of the unknown resistance X?
    A4 ΩB6 ΩC9 ΩD15 Ω
14. Q14. A meter bridge is balanced with a resistance of 15 Ω in the left gap and an unknown resistance X in the right gap. The jockey makes contact at 60 cm from the left end of the meter bridge wire. What is the value of the unknown resistance X?
    A22.5 ΩB40 ΩC10 ΩD9 Ω
15. Q15. In a Wheatstone bridge circuit, four resistors are connected: R₁ = 5 Ω, R₂ = 10 Ω, R₃ = 15 Ω, and R₄ is unknown. When the galvanometer shows zero deflection (balanced condition), what is the value of R₄?
    A30 ΩB7.5 ΩC20 ΩD10 Ω
16. Q16. In a Wheatstone bridge circuit, four resistances are arranged as follows: P = 5 Ω, Q = 10 Ω, R = 8 Ω, and S is unknown. The bridge is balanced (galvanometer shows zero deflection). If the positions of the battery and galvanometer are now interchanged, will the bridge remain balanced? If yes, what is the value of S?
    ANo, the bridge will not be balancedBYes, S = 16 ΩCYes, S = 4 ΩDYes, S = 6.25 Ω
17. Q17. In a meter bridge experiment, a resistance R is connected in the left gap and a resistance of 15 Ω is connected in the right gap. The null point is obtained at 60 cm from the left end. What is the value of the unknown resistance R?
    A37.5 ΩB22.5 ΩC10 ΩD6 Ω
18. Q18. A meter bridge is balanced when the jockey is at 40 cm from the left end. If a resistance of 6 Ω is in the left gap, what is the unknown resistance in the right gap?
    A10 ΩB9 ΩC4 ΩD15 Ω
19. Q19. In a meter bridge experiment, an unknown resistance X is placed in the left gap and a resistance of 6 Ω is placed in the right gap. The null point is obtained at 40 cm from the left end. What is the value of the unknown resistance X?
    A6 ΩB4 ΩC15 ΩD9 Ω
20. Q20. In a balanced Wheatstone bridge the galvanometer (middle arm) carries no current. If this galvanometer is now removed from the circuit, the current drawn from the battery:
    
    AincreasesBdecreasesCbecomes zeroDstays exactly the same
21. Q21. The figure shows two Wheatstone bridges with their arm values marked. Which bridge is balanced (no galvanometer current)?
    
    ABridge 1BBridge 2Cboth are balancedDneither is balanced
22. Q22. A Wheatstone bridge is balanced. If the cell (battery) and the galvanometer are now interchanged with each other, the bridge will:
    
    Aneed to be rebalancedBremain balancedCshow a large deflectionDdraw zero current from the cell
23. Q23. A Wheatstone bridge (arms $P,Q,R,S$) is balanced when:
    A$PQ=RS$B$P+Q=R+S$C$P/Q=R/S$D$P/R=S/Q$
24. Q24. A Wheatstone bridge with arms $P$, $Q$, $R$ and $S$ (the galvanometer joins the $P$–$Q$ junction to the $R$–$S$ junction) is initially balanced. The following changes are made one at a time: (i) the battery emf is doubled; (ii) the cell and the galvanometer are interchanged; (iii) the galvanometer is replaced by one of larger resistance; (iv) only the resistances in arms $P$ and $Q$ are interchanged with each other. How many of these changes leave the bridge still balanced?
    AOneBTwoCThreeDFour
25. Q25. The metre-bridge shown is used to measure the unknown resistance $X$ (in the left gap) against the known resistance $S$ (in the right gap), and the null point occurs at the position marked on the wire. Because a balance point so close to one end gives a large percentage error, the experiment is to be repeated with a different known resistance so that the null falls near the middle of the wire. The known resistance that should now be used is:
    
    A$40\Omega$B$80\Omega$C$10\Omega$D$20\Omega$
26. Q26. In the metre (slide-wire) bridge shown, an unknown coil $X$ sits in the left gap and a standard box $S$ in the right gap; the jockey first gives a null at the balance length ${\ell }_1$ marked. An extra $10\Omega$ spool is then joined in series with the left-gap coil (nothing else is touched), and the jockey now finds silence at the balance length ${\ell }_2$ marked. Using the balance lengths shown on the figure, the original value of the coil $X$ is:
    
    A$20\Omega$B$30\Omega$C$40\Omega$D$15\Omega$
27. Q27. A potentiometer wire is $4\text{m}$ long and a steady potential difference of $2\text{V}$ is maintained across its full length. The potential gradient along the wire is:
    A$2\text{V/m}$B$0.5\text{V/m}$C$0.25\text{V/m}$D$8\text{V/m}$
28. Q28. In the potentiometer circuit shown, a driver cell ${\epsilon }_0$ (with rheostat Rh) is connected across the uniform wire $A(0)$–$B(L)$, and the test cell $(\epsilon ,r)$ is connected through a galvanometer $G$ to the jockey $J$. On open circuit the test cell balances at the length ${\ell }_1$ marked in the figure. When the resistance box is switched in (connected across the cell's terminals), the balance length falls to ${\ell }_2$. Using the values shown, the internal resistance of the cell is:
    
    A$0.5\Omega$B$1.5\Omega$C$1\Omega$D$2\Omega$
29. Q29. Given below are two statements. Statement I: A potentiometer measures the emf of a cell more accurately than a voltmeter does. Statement II: At the balance point the potentiometer draws no current from the cell, so there is no potential drop across the cell's internal resistance. In the light of the above statements, choose the correct answer:
    ABoth Statement I and Statement II are true and Statement II is the correct explanation of Statement IBBoth Statement I and Statement II are true but Statement II is not the correct explanation of Statement ICStatement I is true but Statement II is falseDStatement I is false but Statement II is true
30. Q30. Which of the following statements is CORRECT regarding a Wheatstone bridge?
    AIn an unbalanced bridge, no current flows through the galvanometer arm if the cell connected to the bridge has zero internal resistance.BThe balance condition of a Wheatstone bridge is R₁R₂ = R₃R₄, where R₁, R₂, R₃, R₄ are the resistances in the four arms.CThe balance condition for a Wheatstone bridge is achieved when the product of resistances in one pair of opposite arms equals the product of resistances in the other pair.DA Wheatstone bridge is considered balanced when the current through the cell connected to the battery arm is zero.
31. Q31. In a Wheatstone bridge circuit, the galvanometer shows null deflection. What does this observation directly imply about the galvanometer arm?
    AThe resistance of the galvanometer is infinitely large.BThe total current from the battery becomes zero.CThe resistances in the ratio arms of the bridge are equal.DThe potential at the two ends of the galvanometer arm is equal.