Question 1

Two long, parallel wires carry currents of different magnitudes. If the amount of current in each wire is doubled, what happens to the magnitude of the force between the wires?

Accepted Answer

The magnitude of the force between the wires is directly proportional to the product of the currents in the wires. Doubling the current in each wire will result in the product of the currents being quadrupled, and therefore the magnitude of the force will also quadruple.

Question 2

A proton moving with a velocity of 4.0 × 10⁴ m/s along the +y-axis enters a magnetic field of 0.20 T directed towards the -x-axis. What is the magnitude force acting on the proton?

Accepted Answer

The answer of A proton moving with a velocity of...

Question 3

What is the magnetic field at the center of a circular loop of wire of radius 4.0 cm when a current of 2.0 A flows in the wire?

Accepted Answer

The answer of What is the magnetic field at the...

Question 4

When you double the number of windings in a solenoid keeping all other parameters (radius, length and current) fixed, the magnetic field at the center of the solenoid will

Accepted Answer

The magnetic field created by a solenoid is directly proportional to the number of windings, so doubling the number of windings will result in the magnetic field also doubling.

Question 5

An electron moves with a speed of 8.0 × 10⁶ m/s along the +x-axis. It enters a region where there is a magnetic field of 2.5 T, directed at an angle of 60° to the +x-axis and lying in the x-y plane. Calculate the magnitude of the acceleration of the electron.

Accepted Answer

The answer of An electron moves with a speed of...

Question 6

A proton is accelerated from rest through 500. V. It enters a magnetic field of 0.300 T oriented perpendicular to its direction of motion. Determine:
(a) the radius of the path it follows.
(b) the frequency with which it moves around this path.

Accepted Answer

The answer of A proton is accelerated from rest through...

Question 7

A long straight wire carrying 15. A is perpendicular to a 0.10 T field. Find the force per meter on the wire.

Accepted Answer

The answer of A long straight wire carrying 15. A...

Question 8

A proton moving eastward with a velocity of 5.0 × 10³ m/s enters a magnetic field of 0.20 T pointing northward. What is the magnitude and direction of the force that acts on the proton?

Accepted Answer

The force on a charged particle moving in a magnetic field is given by the equation:
F = qvB sin(theta)
where F is the force, q is the charge on the particle, v is the velocity of the particle, B is the magnetic field, and theta is the angle between the velocity and magnetic field vectors.

In this case, the proton has a positive charge and is moving eastward, which is perpendicular to the northward magnetic field. Therefore, the angle between the velocity and magnetic field vectors is 90 degrees and sin(theta) = 1. Plugging in the given values, we get:
F = (1.6 x 10^-19 C)(5.0 x 10^13 m/s)(0.20 T)(1) = 1.6 x 10^-16 N

Since the force is perpendicular to both the velocity and the magnetic field, it acts upwards in the y-direction. Therefore, the answer is B: 1.6 x 10^-16 N upwards.

Question 9

A stationary proton is in a uniform magnetic field of 0.20 T. What is the magnitude of the magnetic force on the proton?

Accepted Answer

The magnetic force on a stationary charge in a magnetic field is zero. The formula for magnetic force is F = qvBsinθ, where q is the charge, v is the velocity, B is the magnetic field, and θ is the angle between the velocity and the magnetic field. Since the proton is stationary (v = 0), the magnetic force on it is zero.

Question 10

An electron traveling due North with speed 4 × 10⁵ m/s enters a region where the earth's magnetic field has the magnitude 5 × 10^-5 T and is directed downward at 45° below horizontal. What magnitude force acts on the electron?

Accepted Answer

The answer of An electron traveling due North with speed...

Question 11

An ion enters a mass spectrometer which has a 0.18 Tesla field perpendicular to
an electric field of 1.6 kV/m and selects a velocity. The same magnetic field is then
used to deflect the singly charged ion into a circular path of radius 12.5 cm.
(a) What velocity was selected?
(b) What was the ion mass?

Accepted Answer

The answer of An ion enters a mass spectrometer which...

Question 12

A proton moving at 5.0 × 10⁴ m/s horizontally enters a region where a magnetic field of 0.12 T is present, directed vertically downward. What magnitude force acts on the proton?

Accepted Answer

The answer of A proton moving at 5.0 × 10⁴...

Question 13

A proton moving with a velocity of 4.0 × 10⁴ m/s enters a magnetic field of 0.20 T. If the angle between the velocity of the proton and the direction of the magnetic field is 60°, what is the magnitude of the force on the proton?

Accepted Answer

The force on a charged particle moving with a velocity v in a magnetic field B can be calculated using the formula F = qvBsinθ, where q is the charge of the particle and θ is the angle between v and B.

In this case, the charge on the proton is the elementary charge e, which is 1.60 × 10^-19 C. Substituting the given values, we get:

F = evBsinθ = (1.60 × 10^-19 C) × (4.0 × 10^14 m/s) × (0.20 T) × sin 60°

F = 1.12 × 10^-4 N

Rounding off to the appropriate number of significant figures, we get:

F = 1.1 × 10^-15 N

Therefore, the best choice is C.

Question 14

A circular loop of wire of cross-sectional area 0.12 m² consists of 200. turns, each carrying 0.50 A. It is placed in a magnetic field of 0.050 T oriented at 30° to the plane of the loop. What torque acts on the loop?

Accepted Answer

The answer of A circular loop of wire of cross-sectional...

Question 15

Ten meters away from a long straight wire, the field is 10^-4 Tesla. What current flows through the wire?

Accepted Answer

The answer of Ten meters away from a long straight...

Question 16

What is the magnetic moment of a rectangular loop of 120 turns that carries 6.0 A if its dimensions are 40. mm × 8.0 cm?

Accepted Answer

The answer of What is the magnetic moment of a...

Question 17

A proton is projected with a velocity of 7.0 × 10³ m/s into a magnetic field of 0.60 T perpendicular to the motion of the proton. What is the force that acts on the proton?

Accepted Answer

The force on a charged particle moving in a magnetic field is given by F = qvB sin(θ). Here, q = 1.6 × 10^-19 C (charge of a proton), v = 7.0 × 10^3 m/s, B = 0.60 T, and θ = 90° (since the field is perpendicular to the motion). Thus, F = (1.6 × 10^-19 C)(7.0 × 10^3 m/s)(0.60 T) = 6.72 × 10^-16 N, which is approximately 6.7 × 10^-16 N.

Question 18

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?

Accepted Answer

The magnitude of the magnetic force on a charged particle moving perpendicular to a magnetic field is given by F = qvB, where q is the charge of the particle, v is its velocity, and B is the magnetic field strength. In this case, the charge of the electron is -1.6 x 10^-19 C and its velocity is 3.0 x 10^6 m/s. Therefore, the magnetic force on the electron is F = (-1.6 x 10^-19 C)(3.0 x 10^6 m/s)(0.40 T) = -1.92 x 10^-14 N, which has a magnitude of 1.9 x 10^-15 N (since force is a vector quantity and can point in different directions, we take the magnitude of the force). Therefore, the correct answer is (B).

Question 19

Long parallel wires separated by 7.5 cm carry 3.3 Amperes each in opposite directions.
(a) What magnetic force per length acts on the wires?
(b) Find the magnitude of the magnetic field midway between the wires.

Accepted Answer

The answer of Long parallel wires separated by 7.5 cm...

Question 20

An electron moves with a speed of 8.0 × 10⁶ m/s along the +x-axis. It enters a region where there is a magnetic field of 2.5 T, directed at an angle of 60° to the +x-axis and lying in the x-y plane. Calculate the magnitude of the magnetic force on the electron.

Accepted Answer

The magnetic force on a charged particle is given by the equation F = qvBsinθ, where q is the charge of the particle, v is its velocity, B is the magnetic field strength, and θ is the angle between the direction of the velocity and the magnetic field.

In this case, the electron has a charge of -1.6 x 10^-19 C, a velocity of 8.0 x 10^6 m/s, and is moving at an angle of 60° to a magnetic field of 2.5 T.

Using the equation above, we get:

F = (-1.6 x 10^-19 C)(8.0 x 10^6 m/s)(2.5 T)sin(60°)
F = 2.8 x 10^-12 N

Therefore, the magnitude of the magnetic force on the electron is 2.8 x 10^-12 N, which is closest to option C, 2.8 x 10^-12 N.

Quiz 22: Magnetism

Two long, parallel wires carry currents of different magnitudes. If the amount of current in each wire is doubled, what happens to the magnitude of the force between the wires?

A proton moving with a velocity of 4.0 × 104 m/s along the +y-axis enters a magnetic field of 0.20 T directed towards the -x-axis. What is the magnitude force acting on the proton?

What is the magnetic field at the center of a circular loop of wire of radius 4.0 cm when a current of 2.0 A flows in the wire?

When you double the number of windings in a solenoid keeping all other parameters (radius, length and current) fixed, the magnetic field at the center of the solenoid will

An electron moves with a speed of 8.0 × 106 m/s along the +x-axis. It enters a region where there is a magnetic field of 2.5 T, directed at an angle of 60° to the +x-axis and lying in the x-y plane. Calculate the magnitude of the acceleration of the electron.

A proton is accelerated from rest through 500. V. It enters a magnetic field of 0.300 T oriented perpendicular to its direction of motion. Determine: (a) the radius of the path it follows. (b) the frequency with which it moves around this path.

A long straight wire carrying 15. A is perpendicular to a 0.10 T field. Find the force per meter on the wire.

A proton moving eastward with a velocity of 5.0 × 103 m/s enters a magnetic field of 0.20 T pointing northward. What is the magnitude and direction of the force that acts on the proton?

A stationary proton is in a uniform magnetic field of 0.20 T. What is the magnitude of the magnetic force on the proton?

An electron traveling due North with speed 4 × 105 m/s enters a region where the earth's magnetic field has the magnitude 5 × 10-5 T and is directed downward at 45° below horizontal. What magnitude force acts on the electron?

A proton moving at 5.0 × 104 m/s horizontally enters a region where a magnetic field of 0.12 T is present, directed vertically downward. What magnitude force acts on the proton?

A proton moving with a velocity of 4.0 × 104 m/s enters a magnetic field of 0.20 T. If the angle between the velocity of the proton and the direction of the magnetic field is 60°, what is the magnitude of the force on the proton?

A circular loop of wire of cross-sectional area 0.12 m2 consists of 200. turns, each carrying 0.50 A. It is placed in a magnetic field of 0.050 T oriented at 30° to the plane of the loop. What torque acts on the loop?

Ten meters away from a long straight wire, the field is 10-4 Tesla. What current flows through the wire?