What is a magnetic dipole? Describe its magnetic field distribution. A current loop with dimensions much smaller than the distance between the loop and the observation point is called a magnetic dipole. This is because the pattern of its magnetic field lines is similar to that of a permanent magnet, as well as to the … Continue reading What is a magnetic dipole? Describe its magnetic field distribution.

# Category: 5.MAGNETIC FORCES AND TORQUES

# Two infinitely long parallel wires carry currents of equal magnitude. What is the resultant magnetic field due to the two wires at a point midway between the wires, compared with the magnetic field due to one of them alone, if the currents are (a) in the same direction and (b) in opposite directions?

Two infinitely long parallel wires carry currents of equal magnitude. What is the resultant magnetic field due to the two wires at a point midway between the wires, compared with the magnetic field due to one of them alone, if the currents are (a) in the same direction and (b) in opposite directions?

# Exercise 5-5: A square coil of 100 turns and 0.5 m long sides is in a region with a uniform magnetic flux density of 0.2 T. If the maximum magnetic torque exerted on the coil is 4×10 −2 ( N·m), what is the current flowing in the coil?

Exercise 5-5: A square coil of 100 turns and 0.5 m long sides is in a region with a uniform magnetic flux density of 0.2 T. If the maximum magnetic torque exerted on the coil is 4×10 −2 ( N·m), what is the current flowing in the coil?

# Exercise 5-4: A horizontal wire with a mass per unit length of 0.2 kg/m carries a current of 4 A in the +x direction. If the wire is placed in a uniform magnetic flux density B, what should the direction and minimum magnitude of B be in order to magnetically lift the wire vertically upward? [Hint: The acceleration due to gravity is g = −ˆz 9.8 m/s2 . ] Answer: B = ˆy0.49 T.

Exercise 5-4: A horizontal wire with a mass per unit length of 0.2 kg/m carries a current of 4 A in the +x direction. If the wire is placed in a uniform magnetic flux density B, what should the direction and minimum magnitude of B be in order to magnetically lift the wire vertically upward? … Continue reading Exercise 5-4: A horizontal wire with a mass per unit length of 0.2 kg/m carries a current of 4 A in the +x direction. If the wire is placed in a uniform magnetic flux density B, what should the direction and minimum magnitude of B be in order to magnetically lift the wire vertically upward? [Hint: The acceleration due to gravity is g = −ˆz 9.8 m/s2 . ] Answer: B = ˆy0.49 T.

# Concept Question 5-2: The ends of a 10 cm long wire carrying a constant current I are anchored at two points on the x axis, namely x = 0 and x = 6 cm. If thewire lies in the x–y plane in a magnetic field B = ˆyB0 , which of the following arrangements produces a greater magnetic force on the wire: (a) wire is V-shaped with corners at (0, 0), (3, 4), and (6, 0), (b) wire is an open rectangle with corners at (0, 0), (0, 2), (6, 2), and (6, 0).

Concept Question 5-2: The ends of a 10 cm long wire carrying a constant current I are anchored at two points on the x axis, namely x = 0 and x = 6 cm. If thewire lies in the x–y plane in a magnetic field B = ˆyB0 , which of the following arrangements produces … Continue reading Concept Question 5-2: The ends of a 10 cm long wire carrying a constant current I are anchored at two points on the x axis, namely x = 0 and x = 6 cm. If thewire lies in the x–y plane in a magnetic field B = ˆyB0 , which of the following arrangements produces a greater magnetic force on the wire: (a) wire is V-shaped with corners at (0, 0), (3, 4), and (6, 0), (b) wire is an open rectangle with corners at (0, 0), (0, 2), (6, 2), and (6, 0).

# Exercise 5-3: A charged particle with velocity u is moving in a medium with uniform fields E = ˆxE and B = ˆyB. What should u be so that the particle experiences no net force?

Exercise 5-3: A charged particle with velocity u is moving in a medium with uniform fields E = ˆxE and B = ˆyB. What should u be so that the particle experiences no net force?

# Exercise 5-2: A proton moving with a speed of 2 × 10m /s through a magnetic field with magnetic flux density of 2.5 T experiences a magnetic force of magnitude 4 × 10 −13 N . What is the angle between the magnetic field and the proton’s velocity?

Exercise 5-2: A proton moving with a speed of 2 × 10m /s through a magnetic field with magnetic flux density of 2.5 T experiences a magnetic force of magnitude 4 × 10 −13 N . What is the angle between the magnetic field and the proton’s velocity?

# An electron moving in the positive x direction perpendicular to a magnetic field is deflected in the negative z direction. What is the direction of the magnetic field?

An electron moving in the positive x direction perpendicular to a magnetic field is deflected in the negative z direction. What is the direction of the magnetic field?

# What are themajor differences between the electric force Fe a nd the magnetic force Fm ?

What are themajor differences between the electric force Fe a nd the magnetic force Fm ? 1. Whereas the electric force is always in the direction of the electric field, the magnetic force is always perpendicular to the magnetic field. 2. Whereas the electric force acts on a charged particle whether or not it is … Continue reading What are themajor differences between the electric force Fe a nd the magnetic force Fm ?

# How is the direction of the magnetic moment of a loop defined?

How is the direction of the magnetic moment of a loop defined?