Electricity and Magnetism Answers

1.   A tightly wound 1500-turn toroid has an inner radius 1.00 cm and an outer radius 2.00 cm, and carries a current of 2.50A. What is the magnetic field strength at a distance of 1.20 cm from the origin? 

1.   A flux density of 1.5T is produced in a piece of cast steel by a magnetizing force of 1250A/m. Find the relative permeability of the steel under these conditions.

2.   Determine the magnetic field strength required to produce a flux density of 0.3T in an air gap of length 15 mm. 

1.   Determine the magnetic field B in air at a distance of 5 cm of a long wire where a current of 8A flows. 

2.   Find the magnetic field produced by the solenoid if the number of loops is 500 and current passing through on it is 3A (Length of the solenoid is 40 cm). 

Consider a wire of area A = 1m² initially far from any sources of magnetic field. A strong bar magnet with B = 1T near its poles is suddenly inserted into the loop, filling the loop completely. If the time required to insert the magnet is t = 0.1s , what is the approximate value of the induced emf in the loop?

 If the refractive index of a liquid is 4/3. The critical angle for the liquid is ____________?

A solenoid 20 cm long of radius 2cm is wound uniformly with 3000 turns to wire.A current of 2 amp flows through the coil.

What is the solenoid current density

 A person is lying on a diving board 3.00 m above the surface of the water in a swimming pool. She looks at a penny that is on the bottom of the pool directly below her. To her, the penny appears to be a distance of 7.00 m from her. What is the depth of the water at this point?

 An object 0.600 cm tall is placed 16.5 cm to the left of the vertex of a concave spherical mirror having a radius of curvature of 22.0 cm. (a) Draw a principal-ray diagram showing the formation of the image. (b) Determine the position, size, orientation, and nature (real or virtual) of the image.

a. A circular coil has 120 turns of wire in air and has a diameter of 14 cm; the coil is in the same plane as in the sheet. Find the current I that must flow through the wire so that a flux density of 5000µT can be produced at its center

a.   If we immerse a circular coil of 190 mm diameter into a material of relative permeability of 3 and the coil conducts a current of 8A, find the magnetic induction at the center of the coil.

b.   A solenoid with length 65 cm and radius 2 cm has 300 turns of copper wire around a non-magnetic material. If the current flowing through the wire is 3.2A, find the magnetic induction along the center of the solenoid.