Back to the lesson plan builder
Lesson length30 min45 min60 min

Print the plan for yourself; the student sheet prints on its own page after it.

Science lesson plan · 9th grade (Year 10 in England) · 30 minutes

Electrical power, charge and energy

Electricity and magnetism

CCSS NGSS.HS-PS3-1CCSS NGSS.HS-PS3-3England: KS4 Combined Science: Electricity

Objective and success criteria

Students will: Electrical power, charge and energy.

  • I can answer questions on today's skill on my own, without help.
  • I can explain each step and say why it works.
  • I can check my answer and spot a mistake.

Before and after

Needs first: Current, voltage and resistance (V = IR)

Leads to: Power and energy in circuits (P = I²R, E = QV)

Materials: Circuit kits (cells, wires, bulbs), Circuit symbol cards, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).

Warm-up · 4 min

  • Quick retrieval from earlier learning (Current, voltage and resistance (V = IR)). Students answer on mini whiteboards.
  • Show answers together and note who needs support in the main task.
  1. A current of 2 A flows through a 6 Ω resistor. What is the potential difference (voltage) across it, in V? → 12 VPrompt: V = I × R
  2. A 2 V supply is connected across a 2 Ω resistor. What current flows, in A? → 1 APrompt: Rearrange V = I R to find I.
  3. A 48 V battery drives a current of 2 A through a lamp. What is the resistance of the lamp, in Ω? → 24 ΩPrompt: R = V ÷ I

Hook · 3 min

  • Show a circuit with a gap and ask why the bulb doesn't light.
  • Share the objective: Electrical power, charge and energy. Read the success criteria together.

I do: model it · 7 min

  • Work through the example out loud, saying why you do each step, not just what you do.
  • Example: An appliance on US mains (120 V) draws a current of 4 A. What is its power, in W?
  • Step 1: P = 4 × 120 = 480
  • Step 2: So the answer is: 480 W
  • Answer: 480 W
  • Pause after each step and ask a student to say what comes next.

We do: guided practice · 6 min

  • Do these together. Students try each step on whiteboards before you reveal it.
  • Use the hints as prompts rather than giving the answer.
  1. An appliance on US mains (120 V) draws a current of 0.5 A. What is its power, in W? → 60 WPrompt: P = I × V
  2. A current of 0.5 A flows for 300 s. How much charge flows, in coulombs? → 150 CPrompt: Q = I × t

You do: independent practice · 7 min

  • Students work on the student sheet. Circulate and check the first two answers of every student early.
  • Students who finish: write a question of their own for a partner, with the answer.

The 6 questions are on the student sheet below, with answers in the key.

Exit ticket · 3 min

  • Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
  1. A 2000 W device is used for 120 s. How much energy does it transfer, in J? → 240000 JPrompt: E = P × t
  2. A current of 3 A flows for 300 s. How much charge flows, in coulombs? → 900 CPrompt: Q = I × t

Watch out for

  • Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
  • Remembering facts without the reason: ask "why?" and "what is the evidence?"

Support and stretch

Support

  • Review first: Current, voltage and resistance (V = IR).
  • Use concrete materials: circuit kits (cells, wires, bulbs).
  • Give the first step of each question, or a partly worked example to finish.
  • Pair with a confident partner for the guided practice.

Stretch

  • Move on to: Power and energy in circuits (P = I²R, E = QV).
  • Explain a common mistake in writing and how to fix it.
  • Write a word problem that uses today's skill, then solve a partner's.

Homework and more practice

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-9.

Free lesson plan from eurekami.com/lesson-plan-builder

eurekami

Electrical power, charge and energy

Name

Date

Score/ 6

  1. Question 1

    A 100 W device is used for 120 s. How much energy does it transfer, in J?

    AnswerJ

  2. Question 2

    An appliance on UK mains (230 V) draws a current of 2 A. What is its power, in W?

    AnswerW

  3. Question 3

    A current of 2 A flows for 120 s. How much charge flows, in coulombs?

    AnswerC

  4. Question 4

    A 60 W device is used for 120 s. How much energy does it transfer, in J?

    AnswerJ

  5. Question 5

    An appliance on US mains (120 V) draws a current of 10 A. What is its power, in W?

    AnswerW

  6. Question 6

    A current of 0.5 A flows for 30 s. How much charge flows, in coulombs?

    AnswerC

Free from eurekami.com

for the adult only

Answer key: Electrical power, charge and energy

  1. 1. 12000 J

  2. 2. 460 W

  3. 3. 240 C

  4. 4. 7200 J

  5. 5. 1200 W

  6. 6. 15 C