The figure below shows a Wheatstone bridge, a circuit used to precisely measure an unknown resistance R by varying Rvar until the ammeter reads zero current and the bridge is said to be "balanced 3.00 N 1.00 N + 9.00 V Rvar If the bridge is balanced with Rvar = 4.20 W, find the value of the unknown resistance R and the current in the 1.00 N resistor. (Hint: With the bridge balanced, the wire through the ammeter can effectively be removed from the circuit, leaving two pairs of resistors in parallel.) HINT (a) the value of the unknown resistance R (in ohms)

The figure below shows a Wheatstone bridge, a circuit used to precisely measure an unknown resistance R by varying Rvar until the ammeter reads zero current and the bridge is said to be "balanced 3.00 N 1.00 N + 9.00 V Rvar If the bridge is balanced with Rvar = 4.20 W, find the value of the unknown resistance R and the current in the 1.00 N resistor. (Hint: With the bridge balanced, the wire through the ammeter can effectively be removed from the circuit, leaving two pairs of resistors in parallel.) HINT (a) the value of the unknown resistance R (in ohms)

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter9: Current And Resistance

Section: Chapter Questions

Problem 89CP: Consider a resistor made from a hollow cylinder of carbon as shown below. The inner radius of the...

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