PHY_10_3_V2_LP_Measuring magnetic flux density

Long-term plan unit:Magnetic field

School:

Date:

Teacher name:

Grade: 10

Number present:

Absent:

Theme of the lesson

Measuring magnetic flux density

Learning objectives that are achieved at this lesson (Subject Programme reference)

·         To explain the physical meaning of magnetic induction vector based on problem solving and modern technological advances (magnetic levitation train, etc.)

Lesson objectives

By the end of this lesson, students will be able to:

Know that the size of the force also depends on the size of the magnetic field;

Define magnetic flux density and the tesla;

Understand how the force on a current-carrying conductor can be used to measure the flux density of a magnetic field using a current balance;

Assessment criteria

Knowledge

Define magnetic flux density and the tesla;

Know that the size of the force also depends on the size of the magnetic field;

Understanding

Understand how the force on a current-carrying conductor can be used to measure the flux density of a magnetic field using a current balance;

Application

Can set up apparatus then measure the flux density;

Analysis

Describe the methods of measuring magnetic flux density;

Language objectives

Subject-specific vocabulary & terminology

magnetic field direction

magnetic force

current-carrying conductor

Useful set(s) of phrases for dialogue/writing

Currents in the same direction attract each other, currents in opposite directions repel each other.

Type of differentiation

Differentiated poster-session , Collaborative Learning, Progressive Task with Digital resources

Values instilled at the lesson

Safety, Consideration to others, Co-operation, Opportunity for Life-Long Learning, Academic Integrity and Transparency, Respect for Self and Others

Cross-curricular links

·         Chemistry: atom model

·         Mathematics: calculations

ICT skills

Research skills, use of video as introduction

Previous learning

Grade 8: magnetic fields; representation of fields by field lines; fields of permanent magnets

Grade 8: electrical equations: V = IR, P = IV

Course of the lesson

Planned stages of the lesson

Planned activities at the lesson

Resources

Beginning

(0-3 min)

     (4-6 min)

Teacher:

-Introduces the topic of day and spelling out the learning outcome they will possess after the study.

1. Organizational moment to acquaint students with the

·         The theme of the lesson

·         The objectives of the lesson

·         The criteria of success for the lesson

·         The plan of events for the lesson

(T) Teacher question.

·         What is the physical meaning of magnetic flux density?

·         How to measure the value of magnetic flux density?

Middle

7-20 min

(E) Experiment. Measuring magnetic flux density using a current balance.

Theory

For a current flowing perpendicular to a magnetic field, the force exerted on the current carrier is F=BIL where F is in newtons, B is in tesla, I is in amperes, and L is the length in metres of the wire in the magnetic field.

In this experiment, the coil experiences a torque due to the force on the end of the wire which runs through the magnetic field. τ=FR where R is the distance from the end of the coil to the pivot on the razor blades. The coil is uniform and the distance, RR to each end is the same.

When the coil is level, the weight of the tape on one end is equal to the force of the magnetic field on the current at the other end of the coil. The magnetic flux density is found from: B=FIL.

·         Apparatus

·         Procedure

·         Analysis

     21-35 min

(f) Formative assessment.

The diagram shows an arrangement that is used to determine the magnetic flux density
between the poles of a magnet.

The magnet is placed on a sensitive top pan balance. A current-carrying wire is placed at right angles to the magnetic field between the poles of the magnet. The force experienced by the current-carrying wire is equal but opposite to the force experienced by the magnet. The magnet
is pushed downward when the wire experiences an upward force.

The length of the wire in the magnetic field is 5.0 cm. The balance reading is 102.00 g when
there is no current in the wire. The balance reading increases to 103.14 g when the current in
the wire is 8.2 A.

a    Show that the force experienced by the wire is equal to 1.1 ´ 10⁻² N.

                                                                                                                 [1]

b    Calculate the magnetic flux density of the magnetic field between the poles of the magnet.                                                                           [3] [3]

Ending

(36-40 min)

At the end of the lesson, learners reflect on their learning:

-           What has been learned

-           What remained unclear

-           What is necessary to work on

Where possible the learners could evaluate their own work as well as the work of their classmates using certain criteria.

Differentiation – how do you plan to give more support? How do you plan to challenge the more able learners?

Assessment – how are you planning to check students’ learning?

Health and safety regulations

·         Multiple Intelligences

-          Visual will watch the video

-          Analytical take information from the texts

·         Differentiation by questioning and dividing in group

·         Worksheet with varied difficulties

Assessment – how are you planning to check students’ learning?

The output for the worksheet will serve as assessment

Questions during the lesson will also serve as formative assessment.

Be careful when use the laser-coder

Reflection

Were the lesson objectives/learning objectives realistic? Did all learners achieve the LO?

If not, why?

Did my planned differentiation work well?

Did I stick to timings?

What changes did I make from my plan and why?

Use the space below to reflect on your lesson. Answer the most relevant questions from the box on the left about your lesson. 

Summary evaluation

What two things went really well (consider both teaching and learning)?

1:

2:

What two things would have improved the lesson (consider both teaching and learning)?

1:

2:

What have I learned from this lesson about the class or achievements/difficulties of individuals that will inform my next lesson?