Exam 20: Induced Voltages and Inductance: Part A

A horizontal wire of length 3.6 m carries a current of 6.0 A and is oriented so that the current direction is 50° S of W.The Earth's magnetic field is due north at this point and has a strength of 0.14 × 10−⁴ T.What is the direction of the force on the wire?

Assume that a uniform magnetic field is directed into this page.If a proton is released with an initial velocity directed from the bottom edge to the top edge of the page,which of the following describes the direction of the resultant force acting on the proton?

A superconducting solenoid is to be designed to generate a magnetic field of 2.50 T.If the solenoid winding has 1000 turns/m,what is the required current? (µ₀ = 4π × 10−⁷ T⋅m/A)

A circular loop carrying a current of 3.0 A is oriented in a magnetic field of 0.35 T.The loop has an area of 0.24 m² and is mounted on an axis,perpendicular to the magnetic field,which allows the loop to rotate.What is the torque on the loop when its plane is oriented at a 50° angle to the field?

A proton moves across the Earth's equator in a northwesterly direction.At this point the Earth's magnetic field has a direction due north and is parallel to the surface.What is the direction of the force acting on the proton at this instant?

An electron moves through a region of crossed electric and magnetic fields.The electric field E = 3200 V/m and is directed straight down.The magnetic field B = 0.80 T and is directed to the left.For what velocity v of the electron into the paper will the electric force exactly cancel the magnetic force?

A proton and an alpha particle are moving perpendicular to a uniform magnetic field with the same speed.If the velocity of the proton is at an angle of 20° with respect to the magnetic field direction,at what angle to the magnetic field direction would the alpha particle be moving if it experiences the same magnitude acceleration as the proton? The alpha particle has 4 times the mass of the proton and twice its charge.

A horizontal wire of length 3.6 m carries a current of 6.0 A and is oriented so that the current direction is 50° S of W.The Earth's magnetic field is due north at this point and has a strength of 0.14 × 10−⁴ T.What is the size of the force on the wire?

An electron is released such that its initial velocity is from right to left across this page.The electron's path,however,is deflected in a direction toward the bottom edge of the page due to the presence of a uniform magnetic field.What is the direction of this field?

A charged particle moving perpendicular to a magnetic field has a magnet force on it.But when an observer moves with the particle,so that the particle has a relative velocity of zero with respect to the observer,one would expect there would be no magnetic force.Yet there is still a force.If it is not a magnetic force,then what is the source of this force?

A 100-m long wire carrying a current of 4.0 A will be accompanied by a magnetic field of what strength at a distance of 0.040 m from the wire? (magnetic permeability in empty space µ₀ = 4π × 10−⁷ T⋅m/A)

Four long wires are perpendicular to the x-y plane.Each wire carries the same magnitude current.Wire 1 goes through point (a,a,0)on the x-y plane,wire 2 goes through the point (-a,a,0),wire 3 goes through the point (-a,-a,0),and wire 4 goes through the point (a,-a,0).Wires 1 and 3 carry their currents in the positive z direction and wires 2 and 4 carry their currents in the -z direction.What is the direction of the resulting magnetic field at the origin?

Three identical bar magnets,each 2 cm long,are placed in a straight line on a frictionless surface with their ends equally spaced with 2 cm between ends.They are constrained so they cannot rotate,but they can slide along the straight line.The left magnet has its north pole nearest the north pole of the middle magnet,and the right magnet has its south pole toward the middle magnet's south pole.Once they are in place and released from rest,which of the following best describes the motion of the magnets?

A square loop of wire has a current going around it.The magnetic field from the current on each side of the loop results in a magnetic force on the wire on the opposite side.Each resulting magnetic force on the opposite side wire

An electron which moves with a speed of 7.5 × 10³ m/s parallel to a uniform magnetic field of 0.40 T experiences a force of what magnitude? (e = 1.6 × 10−¹⁹ C)

A proton,mass 1.67 × 10−²⁷ kg and charge +1.6 × 10−¹⁹ C,moves in a circular orbit perpendicular to a uniform magnetic field of 0.50 T.Find the time for the proton to make one complete circular orbit.

A deuteron,with the same charge but twice the mass of a proton,moves with a speed of 6.0 × 10⁵ m/s perpendicular to a uniform magnetic field of 0.20 T.Which of the paths described below would it follow? (q_p = 1.6 × 10−¹⁹ C and m_d = 3.34 × 10−²⁷ kg)

A proton with initial kinetic energy E is moving in circular motion in a uniform magnetic field.When it has completed one fourth of a revolution,what is its kinetic energy?

Two long parallel wires 40 cm apart are carrying currents of 10 A and 30 A in the same direction.What is the magnitude of the magnetic field halfway between the wires?

The magnetic force on a charged particle moving at a constant speed in a uniform magnetic field will be doubled when the angle between the velocity of the particle and the direction of the magnetic field changes from 25.0° to