Exam 28: Magnetic Fields of Moving Charges

A long wire located at Z = 0 carries current i₁ = 3.00 A to the right as shown.A second long wire located a distance d = 0.240 m above the first wire carries a current i₂ = 1.10 A to the left as shown.Where in the Z direction (in m)does the magnetic field from the two wires sum to zero?

Two wires,A and B,are parallel to each other and separated by a distance of 25 cm.Both wires carry a current of 1.5 A in the same direction.Where is the magnetic field equal to zero?

When using Ampere's Law,which currents can and must be included in the calculation?

A circular piece of wire connected to the terminals of a battery is lying on a table.The surface of the table is in the horizontal plane.As viewed from above,electrons move through the wire in the counterclockwise direction.In which direction is the magnetic field at the center of the circular wire?

A very long wire carrying a current I = 5.0 A is bent into a semi-circle with a diameter of 10 cm as shown in the figure.What is the magnitude of the magnetic field at the point P,halfway between the ends of the straight sections of wire and at the center of curvature of the semi-circle?

Two long wires are parallel to each other.The wires carry currents of different magnitudes.If the amount of current in each wire is halved,the magnitude of the force between the wires will be

Ampere's Law of magnetic fields is analogous to which law for electric fields?

Two parallel wires,separated by the distance of 2 cm,carry the currents I₁ = 1 A and I₂ = 2 A in the same direction.How far from the wire carrying the current I₁ is the magnetic field zero?

The Biot-Savart Law for magnetic fields is analogous to which law for electric fields?

Two long parallel wires are separated by 2.5 mm.The current in one of the wires is twice the other current.If the magnitude of the force on a 2.0-m length of one of the wires is equal to 4.0 µN,what is the larger of the two currents?

An electron is shot from an electron gun with a speed of 5.0 * 10⁵ m/s parallel to and a distance of 2.0 cm above a long straight wire carrying a current of 10A. Determine the magnitude of the acceleration of the electron the instant it leaves the electron gun.

A coil of wire 20 cm length and 200 turns carries a current of 10 A.A bar of titanium (magnetic susceptibility 1.81 x 10^-4)is positioned within the coil.The magnetic field inside the titanium bar is

A 7.5-m long extension cord carries a current of 12 amps.The cord is made of two wires,carrying currents in opposite directions,separated by a distance of 4.9 mm.Find the force between those two wires.

A current of 2.45 A flows along the length of a long solid cylindrical conductor.The radius of the cylinder is 8.5 cm.The current is uniformly distributed through the conductor.Find where,relative to the center of the wire and inside the wire the magnitude of the magnetic field is 2.00 * 10^-6 T.

A long,straight wire is located along the x-axis (y = 0 and z = 0).The wire carries a current of 5.0 A in the +x direction.What is the magnitude of the force on a 2.0 C charged particle located at (+2.0 m,+1.0 m,0),when it has a velocity of 300 m/s in the +x-direction?

Proton A travels northward with a constant velocity.Due north of proton A is proton B,traveling to the east at a different constant velocity.In what direction is the magnetic force on A?

A wire of radius R = 1.5 mm and carries a current.The current density is given by the function J = J₀ (1 - r/R)where r is measured from the center of the wire and J₀ = 1.06 * 10⁵ A/m².Use Ampère's law to find the magnetic field at the surface of the wire.What is the magnitude of B if I = 1A,R = 1.5 mm.

A wire of radius R carries a current I.The current density is given by the function J = J₀ (1 - r/R)where r is measured from the center of the wire and J₀ is a constant.Use Ampère's law to find the magnetic field inside the wire at a distance r < R from the axis.What is the magnitude of B if I = 1A,R = 1.5 mm,and r = 1 mm?

A coaxial wire consists of a copper wire of radius 1 mm surrounded by a copper sheath of inside radius 1.5 mm and an outside radius 2 mm.A 3-A current flows in one direction down the core and in the opposite direction down the sheath.What is the magnitude of the magnetic field at a radius of 3 mm from the center of the wire?

A long solenoid (diameter = 5.00 cm)is wound with 2000 turns per meter of thin wire through which a constant current is maintained.A wire carrying 8.50 A is inserted along the axis of the solenoid.The magnitude of the magnetic field at a point 5.00 mm from the axis is 0.650 mT.What is the current through the solenoid?