Exam 22: Magnetism

A proton travels at a speed of 5.0 × 10⁷ m/s through a 1.0-T magnetic field.What is the magnitude of the magnetic force on the proton if the angle between the proton's velocity and the magnetic field vector is 30°? (e = 1.60 × 10^-19C)

A circular metal loop of radius 10 cm and three long straight wires carry currents of And As shown in the figure.Each of the straight wires is 20 cm from the center of the loop.The axes are shown in the figure,with the +z-axis coming out of the paper.What is the z component of the resultant magnetic field at the center of the loop? (μ₀ = 4π × 10^-7 T ∙ m/A)

If a calculated quantity has units of ,that quantity could be

A flat circular wire loop of area 0.25 m² carries a current of 5.0 A.This coil lies on a horizontal table with the current flowing in the counterclockwise direction when viewed from above.At this point,the earth's magnetic field is 1.2 × 10^-5 T directed 60° below the horizontal.What is the magnitude of the torque that the earth's magnetic field exerts on this loop?

An ideal solenoid of length 10 cm consists of a wire wrapped tightly around a wooden core.The magnetic field strength is Inside the solenoid.If the solenoid is stretched to By applying a force to it,what does the magnetic field become?

A rigid rectangular loop,measuring 0.30 m by 0.40 m,carries a current of 9.9 A,as shown in the figure.A uniform external magnetic field of magnitude 1.8 T in the -x direction is present.Segment CD is in the xz-plane and forms a 19° angle with the z-axis,as shown.What is the y component of the magnetic force on segment AB of the loop?

If a calculated quantity has units of ,that quantity could be

Which one of the following statements is correct?

At point P the magnetic field due to a long straight wire carrying a current of 2.0 A is 1.2 µT.How far is P from the wire? (μ₀ = 4π × 10^-7 T ∙ m/A)

A straight 1.0-m long wire is carrying a current.The wire is placed perpendicular to a magnetic field of strength 0.20 T.If the wire experiences a force of 0.60 N,what is the current in the wire?

A flat circular coil of wire having 200 turns and diameter 6.0 cm carries a current of 7.0 A.It is placed in a magnetic field of With the plane of the coil making an angle of 30° with the magnetic field.What is the magnitude of the magnetic torque on the coil?

Three long parallel wires each carry 2.0-A currents in the same direction.The wires are oriented vertically,and they pass through three of the corners of a horizontal square of side 4.0 cm.What is the magnitude of the magnetic field at the fourth (unoccupied)corner of the square due to these wires? (μ₀ = 4π × 10^-7 T ∙ m/A)

An electron moves with a speed of 3.0 × 10⁴ m/s perpendicular to a uniform magnetic field of 0.40 T.What is the magnitude of the magnetic force on the electron? (e = 1.60 × 10^-19C)

A thin copper rod 1.0 m long has a mass of 0.050 kg and is in a magnetic field of 0.10 T.What minimum current in the rod is needed in order for the magnetic force to balance the weight of the rod?

A charged particle moving along the +x-axis enters a uniform magnetic field pointing along the +z-axis.Because of an electric field along the +y-axis,the charge particle does not change velocity.What is the sign of this particle?

An electron moves with a speed of 5.0 × 10⁴ m/s perpendicular to a uniform magnetic field of magnitude 0.20 T.What is the magnitude of the magnetic force on the electron? (e = 1.60 × 10^-19C)

Two long parallel wires are placed side-by-side on a horizontal table.If the wires carry current in the same direction,

A charged particle is observed traveling in a circular path of radius R in a uniform magnetic field.If the particle were traveling twice as fast,the radius of the circular path would be

A ring with a clockwise current (as viewed from above the ring)is situated with its center directly above another ring,which has a counter-clockwise current,as shown in the figure.In what direction is the net magnetic force exerted on the top ring due to the bottom ring?

How many turns should a 10-cm long ideal solenoid have if it is to generate a 1.5-mT magnetic field when 1.0 A of current runs through it? (μ₀ = 4π × 10^-7 T ∙ m/A)