Download Ch 21 HW: Problem 21.1 - Charged Particles in Magnetic Fields An

Ch 21 HW: Problem 21.1 - Charged Particles in Magnetic Fields
An alpha particle has a mass of 6.64 x 10-27 kg and a charge of +2e. It is accelerated from rest
through a potential difference of 480 kV, and it is moving in the +x direction at its final speed
when it enters a region of uniform magnetic field of magnitude 0.145 T in the -y direction.
a) What is the final speed of the alpha particle after passing through the 480 kV potential
difference?
b) What is the magnitude and direction of the magnetic force acting on the particle as it first
enters the region of uniform magnetic field?
c) What is the radius of its circular path once the particle is in the magnetic field?
Ch 21 HW: Problem 21.2 - Currents and Current Loops in Magnetic Fields
The loop of wire shown below carries of current of I = 4.70 A. You can assume it is a right
triangle. A uniform magnetic field is directed parallel as shown and has a magnitude of 1.80 T.
(a) Find the magnitude and direction of the magnetic force exerted on each side of the triangle.
(b) Determine the magnitude and direction of the net force exerted on the triangle.
(c) Determine the magnitude of the net torque exerted on the triangle.
Ch 21 HW: Problem 21.3 - Currents and Current Loops in Magnetic Fields
The rectangular loop in the drawing consists of 75 turns and carries a current of
I = 4.4 A. A 1.8-T magnetic field is directed along the +y axis. The loop is free to rotate about
the z axis.
(a) Determine the magnitude of the net torque exerted on the loop.
(b) Will the 35° angle will increase or decrease as the loop rotates in response to the torque?
Explain.
Ch 21 HW: Problem 21.4 - Magnetic Fields Generated by Currents and Current Loops
Four long, parallel wires carry equal currents of 8.00 A. Below is an end-on view of the
arrangement. The direction of the current is into the page for wires A and B and out of the page
for wires C and D.
Calculate the magnitude and direction of the net magnetic field at point P, located at the
center of the square.
b) Calculate the magnitude and direction of the magnetic force per unit length on wire D due to
each of the other three wires. You don’t need to combine them, just find the force due to
wire A, the force due to wire B and the force due to wire C.
a)
Ch 21 HW: Problem 21.5 - Magnetic Fields Generated by Currents and Current Loops
The drawing below shows two perpendicular, long, straight wires, both of which lie in the plane
of the page. The current in each of the wires is I = 2.6 A.
a) Find the magnitude and direction of the net magnetic field at points A and B.
b) An alpha particle (see problem 21.1) is moving through point A with a velocity of 3.5 x 105
m/s in the +x direction. What is the magnitude and direction of the acceleration felt by this
particle?