Question

The circuit in figure consists of wires at the top and bottom and identical springs as the left and right sides. The wire at the bottom has a mass of $10\, g$ and is $5\, cm$ long. The wire is hanging as shown in the figure. The springs stretch $0.5\, cm$ under the weight of the wire and the circuit has a total resistance of $12 \, \Omega$. When the lower wire is subjected to a static magnetic field, the springs, stretch an additional $0.3\, cm$. The magnetic field is

• A. 0.6 T and directed out of page
• B. 1.2 T and directed into the plane of page
• C. 0.6 T and directed into the plane of page
• D. 1.2 T and directed out of page

Answer 1

Answer: (A)

0.6 T and directed out of page

Answer 2

Answer (a) 0.6 T and directed out of page