Question 1

A straight wire that is 0.60 m long is carrying a current of 2.0 A.It is placed in a uniform magnetic field of strength 0.30 T.If the wire experiences a force of 0.18 N,what angle does the wire make with respect to the magnetic field?
A) 25°
B) 30°
C) 35°
D) 60°
E) 90°

Accepted Answer

The force on a current-carrying wire in a magnetic field is given by the formula F = BIL sinθ, where B is the magnetic field strength, I is the current, L is the length of the wire, and θ is the angle between the wire and the magnetic field.

We are given B = 0.30 T, I = 2.0 A, L = 0.60 m, and F = 0.18 N. Solving for sinθ, we get:

sinθ = F / (BIL) = 0.18 / (0.30 x 2.0 x 0.60) = 0.50

Taking the inverse sine, we get:

θ = sin^-1(0.50) ≈ 30°

Therefore, the wire makes an angle of approximately 30° with respect to the magnetic field. Answer: B.

Question 2

A thin copper rod that is 1.0 m long and has a mass of 0.050 kg is in a magnetic field of 0.10 T. What minimum current in the rod is needed in order for the magnetic force to cancel the weight of the rod?
A) 1.2 A
B) 2.5 A
C) 4.9 A
D) 7.6 A
E) 9.8 A

Accepted Answer

The magnetic force ($F_m$) needed to cancel the weight of the rod ($F_g$) can be calculated using the formula $F_m = BIL$, where $B$ is the magnetic field strength, $I$ is the current, and $L$ is the length of the rod. The weight of the rod is given by $F_g = mg$, where $m$ is the mass of the rod and $g$ is the acceleration due to gravity (approximately $9.8 \, \text{m/s}^2$). Setting $F_m = F_g$, we get $BIL = mg$. Solving for $I$, we find $I = \frac{mg}{BL}$. Substituting the given values ($m = 0.050 \, \text{kg}$, $B = 0.10 \, \text{T}$, $L = 1.0 \, \text{m}$, and $g = 9.8 \, \text{m/s}^2$), we get $I = \frac{0.050 \times 9.8}{0.10 \times 1.0} = 4.9 \, \text{A}$.

Question 3

A rigid rectangular loop,which measures 0.30 m by 0.40 m,carries a current of 5.5 A,as shown in the figure.A uniform external magnetic field of magnitude 2.9 T in the negative x direction is present.Segment CD is in the xz-plane and forms a 35° angle with the z-axis,as shown.Find the magnitude of the external torque needed to keep the loop in static equilibrium. 
A) 1.1 N • m
B) 0.73 N • m
C) 1.3 N • m
D) 1.4 N • m
E) 1.6 N • m

Accepted Answer

The answer of A rigid rectangular loop,which measures 0.30 m...

Question 4

A doubly charged ion (charge 2e)with velocity 6.9 × 10⁶ m/s moves in a circular path of diameter 60)0 cm in a magnetic field of 0.80 T in a mass spectrometer. What is the mass of this ion? (e = 1.60 × 10^-19C) A) 11 × 10^-27 kg B) 6.7 × 10^-27 kg C) 4.5 × 10^-27 kg D) 3.3 × 10^-27 kg

Accepted Answer

The answer of A doubly charged ion (charge 2e)with velocity...

Question 5

An L-shaped metal machine part is made of two equal-length segments that are perpendicular to each other and carry a 4.50-A current as shown in the figure.This part has a total mass of 3.80 kg and a total length of 3.00 m,and it is in an external 1.20-T magnetic field that is oriented perpendicular to the plane of the part,as shown.What is the magnitude of the NET magnetic force that the field exerts on the part? 
A) 8.10 N
B) 11.5 N
C) 16.2 N
D) 22.9 N
E) 32.4 N

Accepted Answer

The answer of An L-shaped metal machine part is made...

Question 6

A wire segment 1.2 m long carries a current I = 3.5 A and is oriented as shown in the figure.A uniform magnetic field of magnitude 0.50 T pointing toward the -x direction is present as shown.The +z-axis points directly into the page.What is the magnetic force vector on the wire segment? 
A) +1.6 N 
B) -1.6 N 
C) +1.6 N 
D) (+1.3  - 1.6
 ) N
E) (-1.3  + 1.6
 N

Accepted Answer

The answer of A wire segment 1.2 m long carries...

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 points A to E,as shown in the figure.It is placed in a uniform magnetic field of 0.75 T in the same plane,directed as shown on the right side of the figure.The figure indicates the dimensions of the wire.What are the magnitude and direction of the force acting on  
(a)section AB of this wire?
(b)section BC of this wire?
(c)section CD of this wire?
(d)section DE of this wire?
(e)the entire wire?

Accepted Answer

The answer of A wire in the shape of an...

Question 8

Alpha particles (charge = +2e,mass = 6.68 × 10^-²⁷ kg,e = 1.60 × 10^-19C)0.87 μs. A) 0.44 μs. B) 0.67 μs. C) are accelerated in a cyclotron to a final orbit radius of 0.90 m. The magnetic field in the cyclotron is 0.30 T. The period of the circular motion of the alpha particles is closest to D) 1.1 μs.

Accepted Answer

The period of circular motion in a cyclotron is given by T = (2πm)/(qB). Substituting the given values, T = (2π * 6.68 × 10^-27 kg) / (2 * 1.60 × 10^-19 C * 0.30 T) ≈ 0.44 μs.

Question 9

A proton is first accelerated from rest through a potential difference V and then enters a uniform 0.750-T magnetic field oriented perpendicular to its path.In this field,the proton follows a circular arc having a radius of curvature of 1.84 cm.What was the potential difference V? (m_proton = 1.67 × 10^-27 kg, e = 1.60 × 10^-19 C)

Accepted Answer

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

Question 10

As shown in the figure,a small particle of charge q = -7.0 × 10^-6 C and mass m = 3.1 × 10^-12 kg has velocity v₀ = 9.4 × 10³ m/s as it enters a region of uniform magnetic field.The particle is observed to travel in the semicircular path shown,with radius R = 5.0 cm.Calculate the magnitude and direction of the magnetic field in the region.

Accepted Answer

The answer of As shown in the figure,a small particle...

Question 11

An electron enters a magnetic field of 0.75 T with a velocity perpendicular to the direction of the field.At what frequency does the electron traverse a circular path? (m_el = 9.11 × 10^-31 kg,e = 1.60 × 10^-19C) A) 2.1 × 10¹⁰ Hz B) 4.8 × 10^-7 Hz C) 2.1 × 10¹⁴ Hz D) 4.8 × 10^-11 Hz

Accepted Answer

The frequency (f) of circular motion can be calculated using the formula f = Bq/(2πm), where B is the magnetic field strength, q is the charge of the particle (in this case, the charge of an electron), and m is the mass of the particle (in this case, the mass of an electron). Plugging in the given values, we get: f = (0.75 T * 1.60 × 10^-19 C) / (2π * 9.11 × 10^-31 kg) = 2.1 × 10^10 Hz. Note that this is the same as 2.1 GHz, or 2.1 billion hertz. Therefore, the best choice is A, 2.1 × 10^10 Hz (or 2.1 GHz).

Question 12

A straight 15.0-g wire that is 2.00 m long carries a current of 8.00 A.This wire is aligned horizontally along the west-east direction with the current going from west to east.You want to support the wire against gravity using the weakest possible uniform external magnetic field.
(a)Which way should the magnetic field point?
(b)What is the magnitude of the weakest possible magnetic field you could use?

Accepted Answer

The answer of A straight 15.0-g wire that is 2.00...

Question 13

A wire segment 1.2 m long carries a current I = 3.5 A,and is oriented as shown in the figure.The +x-axis points directly into the page.A uniform magnetic field of magnitude 0.50 T pointing toward the -x direction is present as shown.What is the magnetic force vector on the wire segment? 
A) (+1.1  - 1.8
 ) N
B) (-1.1  + 1.8
 ) N
C) (-1.1  - 1.8
 ) N
D) (+1.8  - 1.1
 ) N
E) (-1.8  + 1.1
 ) N

Accepted Answer

The answer of A wire segment 1.2 m long carries...

Question 14

A wire along the z-axis carries a current of 6.8 A in the +z direction.Find the magnitude and direction of the force exerted on a 6.1-cm long length of the wire by a uniform magnetic field with magnitude 0.36 T in the -x direction.

Accepted Answer

The answer of A wire along the z-axis carries a...

Question 15

A charged particle of mass 0.0020 kg is subjected to a 6.0 T magnetic field which acts at a right angle to its motion.If the particle moves in a circle of radius 0.20 m at a speed of 5.0 m/s,what is the magnitude of the charge on the particle?
A) 0.0083 C
B) 120 C
C) 0.00040 C
D) 2500 C

Accepted Answer

The answer of A charged particle of mass 0.0020 kg...

Question 16

In a mass spectrometer,a singly-charged particle (charge e)has a speed of 1.0 × 10⁶ m/s and enters a uniform magnetic field of 0.20 T. The radius of the circular orbit of the particle is 0.020 m. What is the mass of this particle? (e = 1.60 × 10^-19C) A) 3.2 × 10^-28 kg B) 6.4 × 10^-28 kg C) 1.7 × 10^-27 kg D) 4.5 × 10^-27 kg

Accepted Answer

The answer of In a mass spectrometer,a singly-charged particle (charge...

Question 17

A wire carries a 4.0-A current along the +x-axis through a magnetic field  = (5.0 
+ 7)0 
)T) If the wire experiences a force of 30 N 
As a result,how long is the wire?
A) 1.1 m
B) 0.87 m
C) 1.5 m
D) 0.63 m

Accepted Answer

The answer of A wire carries a 4.0-A current along...

Quiz 27: Magnetic Interactions

A straight wire that is 0.60 m long is carrying a current of 2.0 A.It is placed in a uniform magnetic field of strength 0.30 T.If the wire experiences a force of 0.18 N,what angle does the wire make with respect to the magnetic field?

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

A doubly charged ion (charge 2e) with velocity 6.9 × 10⁶ m/s moves in a circular path of diameter 60) 0 cm in a magnetic field of 0.80 T in a mass spectrometer. What is the mass of this ion? (e = 1.60 × 10^-19C)

A wire segment 1.2 m long carries a current I = 3.5 A and is oriented as shown in the figure.A uniform magnetic field of magnitude 0.50 T pointing toward the -x direction is present as shown.The +z-axis points directly into the page.What is the magnetic force vector on the wire segment?

Alpha particles (charge = +2e,mass = 6.68 × 10^-²⁷ kg,e = 1.60 × 10^-19C) 0.87 μs.

An electron enters a magnetic field of 0.75 T with a velocity perpendicular to the direction of the field.At what frequency does the electron traverse a circular path? (m_el = 9.11 × 10^-31 kg,e = 1.60 × 10^-19C)

A wire segment 1.2 m long carries a current I = 3.5 A,and is oriented as shown in the figure.The +x-axis points directly into the page.A uniform magnetic field of magnitude 0.50 T pointing toward the -x direction is present as shown.What is the magnetic force vector on the wire segment?

A wire along the z-axis carries a current of 6.8 A in the +z direction.Find the magnitude and direction of the force exerted on a 6.1-cm long length of the wire by a uniform magnetic field with magnitude 0.36 T in the -x direction.

A charged particle of mass 0.0020 kg is subjected to a 6.0 T magnetic field which acts at a right angle to its motion.If the particle moves in a circle of radius 0.20 m at a speed of 5.0 m/s,what is the magnitude of the charge on the particle?

In a mass spectrometer,a singly-charged particle (charge e) has a speed of 1.0 × 10⁶ m/s and enters a uniform magnetic field of 0.20 T. The radius of the circular orbit of the particle is 0.020 m. What is the mass of this particle? (e = 1.60 × 10^-19C)

A wire carries a 4.0-A current along the +x-axis through a magnetic field = (5.0 + 7) 0 ) T) If the wire experiences a force of 30 N As a result,how long is the wire?

Quiz 27: Magnetic Interactions

A straight wire that is 0.60 m long is carrying a current of 2.0 A.It is placed in a uniform magnetic field of strength 0.30 T.If the wire experiences a force of 0.18 N,what angle does the wire make with respect to the magnetic field?

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

A doubly charged ion (charge 2e) with velocity 6.9 × 106 m/s moves in a circular path of diameter 60) 0 cm in a magnetic field of 0.80 T in a mass spectrometer. What is the mass of this ion? (e = 1.60 × 10-19C)

A wire segment 1.2 m long carries a current I = 3.5 A and is oriented as shown in the figure.A uniform magnetic field of magnitude 0.50 T pointing toward the -x direction is present as shown.The +z-axis points directly into the page.What is the magnetic force vector on the wire segment?

Alpha particles (charge = +2e,mass = 6.68 × 10-27 kg,e = 1.60 × 10-19C) 0.87 μs.

An electron enters a magnetic field of 0.75 T with a velocity perpendicular to the direction of the field.At what frequency does the electron traverse a circular path? (mel = 9.11 × 10-31 kg,e = 1.60 × 10-19C)

A wire segment 1.2 m long carries a current I = 3.5 A,and is oriented as shown in the figure.The +x-axis points directly into the page.A uniform magnetic field of magnitude 0.50 T pointing toward the -x direction is present as shown.What is the magnetic force vector on the wire segment?

A wire along the z-axis carries a current of 6.8 A in the +z direction.Find the magnitude and direction of the force exerted on a 6.1-cm long length of the wire by a uniform magnetic field with magnitude 0.36 T in the -x direction.

A charged particle of mass 0.0020 kg is subjected to a 6.0 T magnetic field which acts at a right angle to its motion.If the particle moves in a circle of radius 0.20 m at a speed of 5.0 m/s,what is the magnitude of the charge on the particle?

In a mass spectrometer,a singly-charged particle (charge e) has a speed of 1.0 × 106 m/s and enters a uniform magnetic field of 0.20 T. The radius of the circular orbit of the particle is 0.020 m. What is the mass of this particle? (e = 1.60 × 10-19C)

A wire carries a 4.0-A current along the +x-axis through a magnetic field = (5.0 + 7) 0 ) T) If the wire experiences a force of 30 N As a result,how long is the wire?

A doubly charged ion (charge 2e) with velocity 6.9 × 10⁶ m/s moves in a circular path of diameter 60) 0 cm in a magnetic field of 0.80 T in a mass spectrometer. What is the mass of this ion? (e = 1.60 × 10^-19C)

Alpha particles (charge = +2e,mass = 6.68 × 10^-²⁷ kg,e = 1.60 × 10^-19C) 0.87 μs.

An electron enters a magnetic field of 0.75 T with a velocity perpendicular to the direction of the field.At what frequency does the electron traverse a circular path? (m_el = 9.11 × 10^-31 kg,e = 1.60 × 10^-19C)

In a mass spectrometer,a singly-charged particle (charge e) has a speed of 1.0 × 10⁶ m/s and enters a uniform magnetic field of 0.20 T. The radius of the circular orbit of the particle is 0.020 m. What is the mass of this particle? (e = 1.60 × 10^-19C)