A magnetic field B is confined to a region r a ≤ and points out of the paper (the z-axis), r = 0 being the centre of the circular region. A charged ring (charge = Q) of radius b, b > a and mass m lies in the x-y plane with its centre at the origin. The ring is free to rotate and is at rest. The magnetic field is brought to zero in time ∆t. Find the angular velocity ω of the ring after the field vanishes.

A magnetic field B is confined to a region r a ≤ and points out of the paper (the z-axis), r = 0 being the centre of the circular region. A charged ring (charge = Q) of radius b, b > a and mass m lies in the x-y plane with its centre at the origin. The ring is free to rotate and is at rest. The magnetic field is brought to zero in time ∆t. Find the angular velocity ω of the ring after the field vanishes.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter12: Sources Of Magnetic Fields

Section: Chapter Questions

Problem 47P: A long, solid, cylindrical conductor of radius 3.0 cm carries a current of 50 A distributed...

See similar textbooks

Similar questions

In a region a non-uniform magnetic field exists such that Bx = 0, By = 0, and Bz = ax, where a is a constant. At some time t, a wire of length L is carrying a current I is located along the x-axis from origin to x = L. Find the magnetic force on the wire at this instant in time.
Consider a current-carrying wire of length L carrying a current of magnitude I from left to right. What is the magnetic field contribution dB⃗ at point P, with coordinates (x,y), due to the current element dl→ at point A, with coordinates (a,0)? Assume that y is positive.
Consider a uniform magnetic field of magnitude 0.2 T which is directed along the direction of the positive x axis. A positron, which was accelerated by a potential difference of 1 kV, enters this region of the magnetic field with a velocity v which forms an angle of 85 with the x axis. For this case in which the path that the positron describes is helical, as shown in Figure 1, determine:a) The radius r of the helical path.b) The pitch p of the helical path.
in what direction will the roop rotate (x-axis or y-axis) and torque magnitude given that it is a square loop with a side length of 4 cm with a current of 1.3 mA initially at rest and lies fltly within the xy plane with center at origin with a uniform magetic field of (2i +3k)mT and the magnetic moment point of the loop is to the k direction
Consider a thin, straight wire of finite length carrying a constant current I and placed along the x axis as shown. Determine the magnitude and direction of the magnetic field at point P due to this current.
Calculate the magnetic field and vector magnetic potential on axis resulting form z-directed magnetic dipole located at z=z0
A +6µC point charge is moving at a constant speed of 8x106 m/s in the +y-direction, relative to a reference frame. At the instant when the point charge is at the origin of this reference frame, what is the magnetic-field it produces at point with coordinates x=0.5m and y=0.5m?
Consider both wires and find the magnetic field at p3 in unit vector notation
The figure below shows the straight section of a long, hollow cylinder with an internal radius a = 2.0 cm and an external radius b = 4.0 cm. The cylinder conducts a current out of the paper plane, and the modulus of current density in the straight section is given by J=cr2, with c= 3, 0 ∙106 A / m4 and r in meters. What is the magnetic field B at a point that is located at a distance r = 3.0 cm from the central axis of the cylinder?
In this problem we will use a 3-dimensional Cartesian coordinate system with coordinates x, y and z. In the cylindrical region defined by the inequality x2 + y2 < R2 the magnetic field is zero, while outside the cylindrical region the magnetic field points in the +z direction and has constant magnitude B. From the origin of our coordinate system an electron starts with velocity v0= eBR/m in the positive x direction (here e is the elementary charge and m is the mass of the electron). Sketch the trajectory of the electronand find the period of its motion.
Write down an expression for the magnetic electromotive force 'E' generated in a straight conductor of length 'L' moving with velocity 'V' in the magnetic field 'B'.
In Niels Bohr’s 1913 model of the hydrogen atom, the single electron is in a circular orbit of radius 5.29 × 10−11 m and its speed is 2.19 × 106 m/s. (a) What is the magnitude of the magnetic moment due to the electron’s motion? (b) If the electron moves in a horizontal circle, counterclockwise as seen from above, what is the direction of this magnetic moment vector?