Physics-
General
Easy
Question
A long wire AB is placed on a table. Another wire PQ of mass 1.0 g and length 50 cm is set to slide on two rails PS and QR. A current of 50A is passed through the wires. At what distance above AB, will the wire PQ be in equilibrium
- 25 mm
- 50 mm
- 75 mm
- 100 mm
The correct answer is: 25 mm
Suppose in equilibrium wire PQ lies at a distance r above the wire AB
Hence in equilibrium 
Þ 
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