Induced Magnetic Field Homework
Name: _____________________ Class: ____________
1. Current in a loop is counter clock wise. In which direction is induced
magnetic field inside the loop and outside the loop in the plane of paper.
2. A rectangular loop of wire of size ABCD is placed near a long straight wire with side CD at a distance
of 5 cm from it as shown. What is the direction of the net force exerted on the loop? How does your
answer change if the current in the loop is reversed?
3. A long straight wire carries current as shown. Two electrons move with velocities that are parallel and
perpendicular to the current. Find the direction of the magnetic force experienced by each electron.
4. Four long straight parallel wires carry equal currents directed vertically out of the page. They are arranged
on the corners of a square as shown in the figure below.
The direction of the resultant magnetic force exerted on the wire labelled X is
A. south.
B. north.
C. west.
D. east.
5. The currents in two parallel wires are I and 3I in the directions shown in the diagram below.
The magnetic force on wire 2 due to the current in wire 1 is F. The magnitude
of the force on wire 1 due to the current in wire 2 is
A.
B.
C.
D.
F/3.
F/2.
F.
3F.
6. A long, straight current-carrying wire is placed normal to the plane of the page. The current in the
wire is into the plane of the page.
Which of the following diagrams best represents the magnetic field around the wire?
7. The diagram below shows two long parallel wires, 1.0 m apart, on the plane of the page. Each wire
carries a current I in the same direction.
Point P is on the plane of the page midway between the two wires. The magnitude of the magnetic field
strength at point P due to wire 1 alone is B0.
The magnitude of the magnetic field strength at point P due to both wires is
A. 0.
B. ½ B0 .
C. B0.
D. 2 B0 .
8. The diagram below represents four long straight wires perpendicular to the plane of the paper.
The magnitude of the direct current in each wire is the same. Wires with
+ have current into the plane of the paper and wires with • have current
out of the plane of the paper. Point P is the same distance from each
wire.
Which arrow shows the direction of the magnetic field at P?