Lesson: Magnetic Flux Physics • 9th Grade

In this lesson, we will learn how to determine the magnetic flux through a loop in a magnetic field and recognise changes in the magnetic flux through a loop.

Lesson Plan

Students will be able to

recognize that a uniform magnetic field can be modeled as a set of parallel straight field lines and that the density of magnetic field lines represents the magnitude of a magnetic field,
define the magnetic flux, , through an area, , that intersects the magnetic field lines of a magnetic field, , using the equation , where is the angle between the direction of the magnetic field and the direction perpendicular to all sides of ,
relate the magnetic flux, , through a loop of area and the magnetic flux linkage, , through a coil that consists of loops each of area , using the equation .

Lesson Worksheet

Q1:

A rectangular coil of wire has sides of lengths 25 cm and 45 cm. The coil is placed into a magnetic field of 0.35 T. All the sides of the turns of the coil are perpendicular to the direction of the field. The flux linkage of the coil is 1.55 Wb. How many turns are in the coil? Round your answer to the nearest whole number of turns.

Q2:

Two identical loops of conducting wire are in a uniform magnetic field, as shown in the diagram. How does the magnetic flux through both loops compare?

Q3:

A rectangular coil of wire has sides of lengths 35 cm and 55 cm. The coil contains 50 turns. The coil is placed into a magnetic field of 0.15 T. All the sides of the turns of the coil are perpendicular to the direction of the field. What is the flux linkage of the coil?