PHY_10_5_V2_LP_Ampere force. Left-hand rule

Long-term plan unit:Magnetic field

School:

Date:

Teacher name:

Grade: 10

Number present:

Absent:

Theme of the lesson

Ampere force. Left-hand rule.

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

·         to explain the operating principle of electrical measuring instruments, electric engines;

Lesson objectives

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

·         Know  what factors affects to increase the force on a current-currying conductor in a magnetic field;

·         Understand how the force on a current-currying conductor  can be used to explain the motor effect;

·     Recall and solve problems using the equation F = BIL sin with directions as interpreted by Fleming’s Left Hand Rule;

·         Describe the effects of the magnetic force to  conductors;

·         Use Fleming’s Left Hand Rule to find the direction of the force on a current-currying conductor in a magnetic field;

Assessment criteria

Knowledge

Know  what factors affects to increase the force on a current-currying conductor in a magnetic field;

Understanding

Understand how the force on a current-currying conductor  can be used to explain the motor effect;

Application

Use Fleming’s Left Hand Rule to find the direction of the force on a current-currying conductor in a magnetic field;

Recall and solve problems using the equation F = BIL sin with directions as interpreted by Fleming’s Left Hand Rule;

Analysis

Describe the effects of the magnetic force to  conductors;

Language objectives

Subject-specific vocabulary & terminology

magnetic field direction

magnetic force

current-carrying conductor

Fleming’s Left Hand Rule

Magnetic field direction

Current-carrying conductor

Conventional current

Electrical measuring instrument

Useful set(s) of phrases for dialogue/writing

The thumb represents...

The first finger represents...

The second finger represents…

The magnetic force is perpendicular to...

The principle of electrical measuring instruments…

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

Mathematics: solve problems using the equation F = BIL sin θ;

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)

      (4-10 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)(D) Teacher demonstration-1.

Hang a flexible wire between the poles of a powerful magnet. Connect the wire to a cell and a switch as shown.

ü  What happens when you press the switch briefly?

ü  Does the movement reverse if you reverse the direction of the current?

ü   What happens if you turn over the magnet?

This video shows a simple demonstration of the ‘motor effect’ and shows how to apply Fleming’s left hand Rule:

http://www.youtube.com/watch?v=U9RezsWnPYs

Middle

11-14 min

     15-18 min

19-22 min

(D) Video demonstration.

Demonstrate the force on a current-carrying conductor (‘motor effect’) using a long loose wire between the poles of a strong magnet. As d.c. current is switched on in the wire it ‘jumps’ in a direction at 90 degrees to both the magnetic field lines and the current.

(T)(D)Teacher demonstration-2.

It is necessary to demonstrate the relationship of the Ampere force and the length of the active part of a conductor/current/place of the conductor in a magnetic field.

Teacher changes the length of the active part of a conductor and observes the effect.

Lead learners to derivation of the formula F=BILsinα. Use the Fleming’s Left Hand Rule to find the direction of Ampere force.

Discussion: Factors affecting the force

The previous experiments lead to the conclusion that the force F on the conductor is proportional to the length of wire in the field, L, the current I and the ‘strength’ of the field, represented by the flux density B. (There is also an 'angle factor' to consider, but we will leave this aside for now.

Combining these we get  F = BIL

(It can help students to refer to this force as the ‘BIL force’.)

     23-35 min

(f) Formative assessment.

Suggest that learners solve the problems involving calculation with use of the formula F=BILsinα to calculate the forces acting on current-carrying conductors, magnetic induction vector and angle α. Introduce learners to the unit of measuring magnetic induction vector 1 Tл =1 Н /( m*A), (Tesla).

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?