Question 1

A proton,moving north,enters a magnetic field.Because of this field,the proton curves downward.We may conclude that the $\vec { B }$ field must have a component

Accepted Answer

A) downward. 
B) upward. 
C) towards the east. 
D) towards the west. 
E) towards the north. 
A) downward. 
B) upward. 
C) towards the east. 
D) towards the west. 
E) towards the north.

Question 2

A proton is to orbit Earth at the equator using Earth's magnetic field to exert part of the necessary radial component of the sum of the forces.In what direction should the proton move?

Accepted Answer

A) upward 
B) northward 
C) southward 
D) eastward 
E) westward 
A) upward 
B) northward 
C) southward 
D) eastward 
E) westward

Question 3

A straight wire carries a current of 10 A at an angle of 30° with respect to the direction of a uniform 0.30-T $\vec { B }$ field.Find the magnitude of the magnetic force exerted on a 0.50-m length of the wire.

Accepted Answer

A) 0.75 N 
B) 1.5 N 
C) 3.0 N 
D) 6.0 N 
A) 0.75 N 
B) 1.5 N 
C) 3.0 N 
D) 6.0 N

Question 4

An electron has an initial velocity to the south but is observed to curve upward as the result of a magnetic field.This $\vec { B }$ field must have a component

Accepted Answer

A) to the west. 
B) to the east. 
C) upward. 
D) downward. 
E) to the north. 
A) to the west. 
B) to the east. 
C) upward. 
D) downward. 
E) to the north.

Question 5

An electron is accelerated from rest through a potential difference of 3.75 kV.It enters a region where a uniform 4.0-mT $\vec { B }$ field is perpendicular to the velocity of the electron.Calculate the radius of the path this electron will follow in the magnetic field.(e = 1.60 × 10-19 C,melectron = 9.11 × 10-31 kg)

Accepted Answer

A) 1.2 cm 
B) 2.2 cm 
C) 3.2 cm 
D) 4.2 cm 
E) 5.2 cm 
A) 1.2 cm 
B) 2.2 cm 
C) 3.2 cm 
D) 4.2 cm 
E) 5.2 cm

Question 6

Two long parallel wires carry currents of 20 A and 5.0 A in opposite directions.The wires are separated by 0.20 m.What is the magnitude of the $\vec { B }$ field midway between the two wires? (μ0 = 4π × 10-7 T ∙ m/A)

Accepted Answer

A) 1.0 × 10-5 T 
B) 2.0 × 10-5 T 
C) 3.0 × 10-5 T 
D) 4.0 × 10-5 T 
E) 5.0 × 10-5 T 
A) 1.0 × 10-5 T 
B) 2.0 × 10-5 T 
C) 3.0 × 10-5 T 
D) 4.0 × 10-5 T 
E) 5.0 × 10-5 T

Question 7

A wire in the shape of an "M" lies in the plane of the paper.It carries a current of 2.0 A,flowing from A to E.It is placed in a uniform 0.85-T $\vec { B }$ field in the same plane,directed as shown on the right side of the figure.The figure indicates the dimensions of the wire.Note that AB is parallel to DE and to the baseline from which the $\vec { B }$ field direction is measured.What are the magnitude and direction of the net magnetic force exerted on this wire?

Accepted Answer

A) 0.40 N perpendicular out of the page 
B) 0.10 N perpendicular into the page 
C) 0.40 N perpendicular into the page 
D) 0.10 N perpendicular out of the page 
E) 0.20 N perpendicular out of the page 
A) 0.40 N perpendicular out of the page 
B) 0.10 N perpendicular into the page 
C) 0.40 N perpendicular into the page 
D) 0.10 N perpendicular out of the page 
E) 0.20 N perpendicular out of the page

Question 8

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,Earth's $\vec { B }$ field is 1.2 × 10-5 T directed 60° below the horizontal.What is the magnitude of the torque that Earth's magnetic field exerts on this loop?

Accepted Answer

A) 2.5 × 10-6 N ∙ m 
B) 5.0 × 10-6 N ∙ m 
C) 7.5 × 10-6 N ∙ m 
D) 1.0 × 10-5 N ∙ m 
A) 2.5 × 10-6 N ∙ m 
B) 5.0 × 10-6 N ∙ m 
C) 7.5 × 10-6 N ∙ m 
D) 1.0 × 10-5 N ∙ m

Question 9

A rectangular coil,with corners labeled ABCD,has length L and width w.It is placed between the poles of a magnet,as shown in the figure If there is a current I through this coil in the direction shown,what is the direction of the force exerted on section BC of this coil?

Accepted Answer

A) perpendicular to and into the page 
B) perpendicular to and out of the page 
C) in the direction of the $\vec { B }$ field 
D) in the opposite direction of the $\vec { B }$ field 
E) The force is zero. 
A) perpendicular to and into the page 
B) perpendicular to and out of the page 
C) in the direction of the $\vec { B }$ field 
D) in the opposite direction of the $\vec { B }$ field 
E) The force is zero.

Question 10

A wire in the shape of an "M" lies in the plane of the paper.It carries a current of 2.0 A, from A to E,as shown in the figure.It is placed in a uniform magnetic 0.75-T $\vec { B }$ field in the same plane,directed as shown on the right side of the figure.The figure indicates the dimensions of the wire.Note that AB is parallel to DE and to the baseline from which the $\vec { B }$ field direction is measured.What are the magnitude and direction of the magnetic force exerted on section AB of this wire?

Accepted Answer

A) 0.20 N perpendicular out of the page 
B) 0.40 N perpendicular out of the page 
C) 0.11 N perpendicular out of the page 
D) 0.20 N perpendicular into the page 
E) 0.11 N perpendicular into the page 
A) 0.20 N perpendicular out of the page 
B) 0.40 N perpendicular out of the page 
C) 0.11 N perpendicular out of the page 
D) 0.20 N perpendicular into the page 
E) 0.11 N perpendicular into the page

Question 11

Two long parallel wires placed side-by-side on a horizontal table carry identical size currents in opposite directions.The wire on your right carries current directly toward you,and the wire on your left carries current directly away from you.From your point of view,the $\vec { B }$ field at a point exactly midway between the two wires

Accepted Answer

A) points upward. 
B) points downward. 
C) points toward you. 
D) points away from you. 
E) is zero. 
A) points upward. 
B) points downward. 
C) points toward you. 
D) points away from you. 
E) is zero.

Question 12

A vertical wire carries a current vertically downward.To the east of this wire,the $\vec { B }$ field points

Accepted Answer

A) north. 
B) east. 
C) south. 
D) down. 
A) north. 
B) east. 
C) south. 
D) down.

Question 13

A charged particle of mass 0.0040 kg is enters a $4.0 - 1$ magnetic field with the direction of the field vector at a right angle to its motion.If the particle moves in a circle of radius $0.10 \mathrm {~m}$ at a speed of $2.0 \mathrm {~m} / \mathrm { s }$ what is the magnitude of the charge on the particle?

Accepted Answer

A) 0.020 C 
B) 50 C 
C) 0.00040 C 
D) 2500 C 
A) 0.020 C 
B) 50 C 
C) 0.00040 C 
D) 2500 C

Question 14

The direction of the force exerted on a current-carrying wire in a magnetic field is

Accepted Answer

A) perpendicular only to the current. 
B) perpendicular only to the $\vec { B }$ field. 
C) perpendicular to both the current and the $\vec { B }$ field. 
D) in the direction opposite to the current. 
E) in same direction as the current. 
A) perpendicular only to the current. 
B) perpendicular only to the $\vec { B }$ field. 
C) perpendicular to both the current and the $\vec { B }$ field. 
D) in the direction opposite to the current. 
E) in same direction as the current.

Question 15

At a point 10 m away from a long straight thin wire,the $\vec { B }$ field due to the wire is 0.10 mT.What is the current through the wire? (μ0 = 4π × 10-7 T ∙ m/A)

Accepted Answer

Question 16

At a particular instant,a proton moves toward the east in a uniform $\vec { B }$ field that is directed straight downward.The magnetic force exerted on it is

Accepted Answer

A) zero. 
B) upward. 
C) toward the north. 
D) toward the south. 
E) downward. 
A) zero. 
B) upward. 
C) toward the north. 
D) toward the south. 
E) downward.

A proton,moving north,enters a magnetic field.Because of this field,the proton curves downward.We may conclude that the $\vec { B }$ field must have a component

A proton is to orbit Earth at the equator using Earth's magnetic field to exert part of the necessary radial component of the sum of the forces.In what direction should the proton move?

A straight wire carries a current of 10 A at an angle of 30° with respect to the direction of a uniform 0.30-T $\vec { B }$ field.Find the magnitude of the magnetic force exerted on a 0.50-m length of the wire.

An electron has an initial velocity to the south but is observed to curve upward as the result of a magnetic field.This $\vec { B }$ field must have a component

Two long parallel wires carry currents of 20 A and 5.0 A in opposite directions.The wires are separated by 0.20 m.What is the magnitude of the $\vec { B }$ field midway between the two wires? (μ₀ = 4π × 10^-7 T ∙ m/A)

A rectangular coil,with corners labeled ABCD,has length L and width w.It is placed between the poles of a magnet,as shown in the figure If there is a current I through this coil in the direction shown,what is the direction of the force exerted on section BC of this coil?

A vertical wire carries a current vertically downward.To the east of this wire,the $\vec { B }$ field points

The direction of the force exerted on a current-carrying wire in a magnetic field is

At a point 10 m away from a long straight thin wire,the $\vec { B }$ field due to the wire is 0.10 mT.What is the current through the wire? (μ₀ = 4π × 10^-7 T ∙ m/A)

At a particular instant,a proton moves toward the east in a uniform $\vec { B }$ field that is directed straight downward.The magnetic force exerted on it is

Introduction

Kinematics: Motion in One Dimension

Newtonian Mechanics

Applying Newtons Laws

Circular Motion

Impulse and Linear Momentum

Work and Energy

Extended Bodies at Rest

Rotational Motion

Gases

Static Fluids

Fluids in Motion

First Law of Thermodynamics

Second Law of Thermodynamics

Electric Charge force and Energy

The Electric Field

Dc Circuits

Electromagnetic Induction

Vibrational Motion

Mechanical Waves

Reflection and Refraction

Mirrors and Lenses

Wave Optics

Electromagnetic Waves

Special Relativity

Quantum Optics

Atomic Physics

Nuclear Physics

Particle Physics

Filters

Exam 18: Magnetism

A proton,moving north,enters a magnetic field.Because of this field,the proton curves downward.We may conclude that the B⃗\vec { B }B field must have a component

A proton is to orbit Earth at the equator using Earth's magnetic field to exert part of the necessary radial component of the sum of the forces.In what direction should the proton move?

A straight wire carries a current of 10 A at an angle of 30° with respect to the direction of a uniform 0.30-T B⃗\vec { B }B field.Find the magnitude of the magnetic force exerted on a 0.50-m length of the wire.

An electron has an initial velocity to the south but is observed to curve upward as the result of a magnetic field.This B⃗\vec { B }B field must have a component

Two long parallel wires carry currents of 20 A and 5.0 A in opposite directions.The wires are separated by 0.20 m.What is the magnitude of the B⃗\vec { B }B field midway between the two wires? (μ0 = 4π × 10-7 T ∙ m/A)

A rectangular coil,with corners labeled ABCD,has length L and width w.It is placed between the poles of a magnet,as shown in the figure If there is a current I through this coil in the direction shown,what is the direction of the force exerted on section BC of this coil?

A vertical wire carries a current vertically downward.To the east of this wire,the B⃗\vec { B }B field points

The direction of the force exerted on a current-carrying wire in a magnetic field is

At a point 10 m away from a long straight thin wire,the B⃗\vec { B }B field due to the wire is 0.10 mT.What is the current through the wire? (μ0 = 4π × 10-7 T ∙ m/A)

At a particular instant,a proton moves toward the east in a uniform B⃗\vec { B }B field that is directed straight downward.The magnetic force exerted on it is

Introduction

Kinematics: Motion in One Dimension

Newtonian Mechanics

Applying Newtons Laws

Circular Motion

Impulse and Linear Momentum

Work and Energy

Extended Bodies at Rest

Rotational Motion

Gases

Static Fluids

Fluids in Motion

First Law of Thermodynamics

Second Law of Thermodynamics

Electric Charge force and Energy

The Electric Field

Dc Circuits

Electromagnetic Induction

Vibrational Motion

Mechanical Waves

Reflection and Refraction

Mirrors and Lenses

Wave Optics

Electromagnetic Waves

Special Relativity

Quantum Optics

Atomic Physics

Nuclear Physics

Particle Physics

Filters

A proton,moving north,enters a magnetic field.Because of this field,the proton curves downward.We may conclude that the $\vec { B }$ field must have a component

A straight wire carries a current of 10 A at an angle of 30° with respect to the direction of a uniform 0.30-T $\vec { B }$ field.Find the magnitude of the magnetic force exerted on a 0.50-m length of the wire.

An electron has an initial velocity to the south but is observed to curve upward as the result of a magnetic field.This $\vec { B }$ field must have a component

Two long parallel wires carry currents of 20 A and 5.0 A in opposite directions.The wires are separated by 0.20 m.What is the magnitude of the $\vec { B }$ field midway between the two wires? (μ₀ = 4π × 10^-7 T ∙ m/A)

A vertical wire carries a current vertically downward.To the east of this wire,the $\vec { B }$ field points

At a point 10 m away from a long straight thin wire,the $\vec { B }$ field due to the wire is 0.10 mT.What is the current through the wire? (μ₀ = 4π × 10^-7 T ∙ m/A)

At a particular instant,a proton moves toward the east in a uniform $\vec { B }$ field that is directed straight downward.The magnetic force exerted on it is