PHYSICS_10_23_V1_LP_Ohm's law in complete circuits

Long-term plan unit: Electrostatics

School:

Date:

Teacher name:

Grade: 10

Number present:

absent:

Theme of the lesson

Ohm's law to complete circuit

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

Ø  To apply Ohm's law to complete circuit

Lesson objectives

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

·         Show an understanding of Ohm's law to complete circuit;

·         Explain the physical meaning of Ohm's law to complete circuit of the direct current on the basis of the law of conservation of energy;

·         Can apply Ohm's law to complete circuit in solving problems

Assessment criteria

Knowledge

Know Ohm's law to complete circuit;

Application

Solve problems involving Ohm's law to complete circuit;

Language objectives

Subject-specific vocabulary & terminology

Electromotive force (EMF)

Terminal voltage

Lost voltage

Internal resistance

Load resistance

Useful set(s) of phrases for dialogue/writing

All voltage sources have two fundamental parts: a source of electrical energy that has a characteristic electromotive force (emf), and an internal resistance r.

The emf is the potential difference of a source when no current is flowing.

The numerical value of the emf depends on the source of potential difference.

The internal resistance r of a voltage source affects the output voltage when a current flows.

The voltage output of a device is called its terminal voltage V and is given by V = emf − Ir, where I is the electric current and is positive when flowing away from the positive terminal of the voltage source.

When multiple voltage sources are in series, their internal resistances add and their emfs add algebraically.

Values instilled at the lesson

v  Appreciation for the unique abilities of each learner.

v  Respect for other’s opinion while working in a group.

v  Lifelong learning that theories learned from our discussion could be applied also to practical life.

v  Internationalism – the students must recognize that the discovery of capacitors is made by physicists who came from different countries.

Cross-curricular links

      Visual Literacy Instruction – the students must understand, appreciate and comprehend what they have seen in the presentation and other video materials.

      *Utilization of IT in teaching and learning process.

      Mathematics-knowledge on algebra, fundamentals and higher mathematics are pre-requisites to this lesson

ICT skills

Presentation, Interactive Board

Previous learning

Grade 8: d.c. circuits; V = IR; Ohm’s Law; electrical characteristics; circuit symbols; circuit diagrams; electrical energy and power;

Course of the lesson

Planned stages of the lesson

Planned activities at the lesson

Resources

Beginning

5 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

2. Starter activity: Guess now!

Middle

6-15 min

 16-33 min

 34-38 min

(T) Teacher explanation. Derive the Ohm’s law to complete circuit

There are three ways to arrive at the equation relating EMF, terminal PD, current and internal resistance. It is worth discussing all three, to show their equivalence. The order you take will depend on the approach used previously with the class:

1. As charge goes around the circuit the sum of EMFs must equal the sum of voltage drops leading to:

ε = I R + I r

The terminal voltage is equal to I R so this can be rearranged to give:

V = ε – I r

and interpreted as terminal voltage = EMF – ‘lost volts’

2. Energy is conserved. Imagine a unit of charge, Q, moving around the circuit:

Q ε = Q I R + Q I r

This leads to the same equations as in (1) above.

3. Use Ohm’s law with E ‘driving’ current through the combined resistance (R + r):

I = ε / (R+r) ─ Ohm's law to complete circuit.

Activity. Compare EMF and internal resistance

(f) Formative assessment questions.

Ask learners individually to solve problems on calculation of electric circuits including the short circuit. Assess the consequences of short circuit and suggest how to protect electric circuits from short circuits.

Self assessment.

Students assess yourself by using answer sheet and provide fair and helpful feedback

Students take a portion of the responsibility for monitoring their own progress

Appendix

End

  39-40 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 assess 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

Differentiation can be by task, by outcome, by individual support, by selection of teaching materials and resources taking into account individual abilities of learners (Theory of Multiple Intelligences by Gardner).

Differentiation can be used at any stage of the lesson keeping time management in mind.

Use this section to record the methods you will use to assess what students have learned during the lesson.

Health promoting techniques

Breaks and physical activities used.

Points from Safety rules used at this lesson.

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?