Question

A straight, stiff, horizontal wire of length 46 cm and mass 20 g is connected to a source of emf by light, flexible leads. A magnetic field of 1.33 T is horizontal and perpendicular to the wire. 1)Find the current necessary to float the wire, that is, find the current for which the magnetic force balances the weight of the wire.

Answer 1

Answer:

0.32 A

Explanation:

Weight of the wire = m × g  where m, mass = (20 g / 1000 g) × 1 kg = 0.02 kg  and g = 9.8 m/s²

Magnetic force = I L B sinα and α is 90°

and weight of the wire = magnetic force

0.02 kg × 9.8 m/s² = I × 0.46 m × 1.33 × 1

I, current = 0.02 kg × 9.8 m/s² / ( 0.46 m × 1.33T) = 0.32 A