Question

If the balance length corresponding to points B and C is 40 cm on the potentiometer wire. The balance length corresponding to points C and D is –

• A. 25 cm
• B. 32 cm
• C. 40 cm
• D. 64 cm

Answer 1

Answer: (B)

32 cm

Answer 2

V_B – V_C = I × 5 = f × 40 …. (1)

\ V_C – V_D = I × 4 = f × l …. (2)

$\frac { \mathrm { eq } _ { \cdot 1 } } { \mathrm { eq } \cdot 2 }$ $\frac { 5 } { 4 }$ = $\frac { 40 } { \ell }$ \ l = $\frac { 40 \times 4 } { 5 }$ = 32 cm