A \'Wheatstone bridge\' is a device that measures resistances. In the circuit sh

Question

A 'Wheatstone bridge' is a device that measures resistances. In the circuit shown in the diagram below, R is an unknown resistance. The resistances R1, R2, and R3are variable. A galvanometer, G, can be used to determine when the potential difference between b and c is zero, given that the battery is connected between a and d. The variable resistances are adjusted until there is no current in the galvanometer when the switch, S, is closed. Suppose that the galvanometer reads zero for a particular circuit, determine an expression for R in terms of R1, R2, and R3. To check your answer, consider the case when R1= 56 ?, R2= 33 ?, and R3= 63 ?. What is the value of the unknown resistor R when the galvanometer reads zero as the switch is closed?

Explanation / Answer

r/r2=r1/r3 r=r1r2/r3 r=56*33/63 =29.33ohm

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.