Exam 8: Magnetic Forces

A magnetic field of 2.00 T is applied to a bubble chamber to make the tracks of protons and other charged particles identifiable by the radius of the circles they move in.If a high-energy proton moves along an arc of a 3.30-m circle, what is the momentum of the proton? [q = 1.60 *10-19 C, m = 1.67 * 10-27 kg]

A straight wire is bent into the shape shown.Determine the net magnetic force on the wire when the current I travels in the direction shown in the magnetic field

A positively charged particle has a velocity in the negative z direction at point P.The magnetic force on the particle at this point is in the negative y direction.Which one of the following statements about the magnetic field at point P can be determined from this data?

A segment of wire carries a current of 25 A along the x axis from x = -2.0 m to x = 0 and then along the y axis from y = 0 to y = 3.0 m.In this region of space, the magnetic field is equal to 40 mT in the positive z direction.What is the magnitude of the force on this segment of wire?

A particle (m = 3.0 $\mu$ g, q = 5.0 $\mu$ C) moves in a uniform magnetic field given by () mT.At t = 0 the velocity of the particle is equal to () m/s.The subsequent path of the particle is:

A velocity selector uses a fixed electric field of magnitude E and the magnetic field is varied to select particles of various energies.If a magnetic field of magnitude B is used to select a particle of a certain energy and mass, what magnitude of magnetic field is needed to select a particle of equal mass but twice the energy?

What is the magnitude of the magnetic force on a charged particle (Q = 5.0 $\mu$ C) moving with a speed of 80 km/s in the positive x direction at a point where Bx = 5.0 T, By = -4.0 T, and Bz = 3.0 T?

Three particles of equal charge, X, Y, and Z, enter a uniform magnetic field B.X has velocity of magnitude v parallel to the field.Y has velocity of magnitude v perpendicular to the field.Z has equal velocity components v parallel and perpendicular to the field.Rank the radii of their orbits from least to greatest.

Two single charged ions moving perpendicularly to a uniform magnetic field (B = 0.40 T) with speeds of 5000 km/s follow circular paths that differ in diameter by 5.0 cm.What is the difference in the mass of these two ions?

At what speed would a proton need to circle the Earth at a height of 1000 km above the equator if the Earth's magnetic field is horizontal and directed north-south, with an intensity of 4.00 * 10-8 T? (The radius of the Earth is 6400 km and the charge and mass of the proton are q = 1.60 * 10-19 C and mp = 1.67 * 10-27 kg.Ignore relativistic corrections.)

An electron follows a circular path (radius = 15 cm) in a uniform magnetic field (magnitude = 3.0 G).What is the period of this motion?

A thin ribbon of a silver alloy 2.00-cm wide and 0.015 0-mm thick carries a current of 6.98 A perpendicular to a magnetic field.The Hall voltage is found to be 1.24 * 10-4 V when the magnetic field is 2.50 T.Calculate n, the number of charge carriers per cubic metre.

A 500-eV electron and a 300-eV electron trapped in a uniform magnetic field move in circular paths in a plane perpendicular to the magnetic field.What is the ratio of the radii of their orbits?

A charged particle moves in a region of uniform magnetic field along a helical path (radius = 5.0 cm, pitch = 12 cm, period = 5.0 ms).What is the speed of this particle as it moves along this path?

A straight wire carries a current of 40 A in a uniform magnetic field (magnitude = 80 mT).If the force per unit length on this wire is 2.0 N/m, determine the angle between the wire and the magnetic field.

A stream of electrons passes through a velocity filter where the crossed magnetic and electric fields are 0.020 T and 5.00 * 104 V/m, respectively.Find the kinetic energy (in electron volts) of the electrons passing through the filter.[1 eV = 1.60 *10-19 J]

A coaxial cable has an inner cylindrical conductor surrounded by cylindrical insulation and an outer cylindrical conducting shell.The outer shell carries the same current but in the opposite direction from that in the inner conductor as shown.If the coaxial cable sits in a uniform magnetic field directed upwards with respect to the cable, the effect of the field on the cable is:

A uniform magnetic field of 0.50 T is directed along the positive x axis.A proton moving with a speed of 60 km/s enters this field.The helical path followed by the proton shown has a pitch of 5.0 mm.Determine the angle between the magnetic field and the velocity of the proton.

The magnetic field in a region of space is parallel to the surface of a long flat table.Imagine that this page is lying flat on the table.When current is present in the coil, which is lying on the table, the coil tends to rotate so that the left side moves up and the right side moves down.The magnetic field is:

A magnetic field is directed out of the page.Two charged particles enter from the top and take the paths shown in the figure below.Which statement is correct?