Science lesson plan · 10th grade (Year 11 in England) · 45 minutes
Use energy conservation to find speeds and heights
Energy
CCSS NGSS.HS-PS3-1CCSS NGSS.HS-PS3-2England: GCSE Combined Science: Energy
Objective and success criteria
Students will: Use energy conservation to find speeds and heights.
- 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: Kinetic and gravitational potential energy; Conservation of energy and wasted energy
Leads to: the next skill in this area.
Materials: Wind-up toys or a pendulum, Energy transfer diagrams, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Kinetic and gravitational potential energy; Conservation of energy and wasted energy). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- What is the kinetic energy of a 4 kg object moving at 5 m/s? Use Eₖ = ½ m v². → 50 JPrompt: Square the speed first.
- A kettle is supplied with 1200 J of energy. It transfers 240 J usefully. How much energy is wasted, in J? → 960 JPrompt: Energy is conserved: input = useful output + wasted output.
- An object of mass 2 kg is lifted 10 m. How much gravitational potential energy does it gain? Use Eₚ = m g h with g = 9.8 N/kg. → 196 JPrompt: Multiply mass, gravitational field strength and height.
Hook · 5 min
- Wind up a toy or stretch an elastic band and ask where the energy goes.
- Share the objective: Use energy conservation to find speeds and heights. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: A ball is dropped from a height of 5 m. Ignoring air resistance, how fast is it moving just before it hits the ground, in m/s? (g = 9.8 N/kg; give 1 decimal place)
- Step 1: v = √(2 × 9.8 × 5) = √98 = 9.9
- Step 2: So the answer is: 9.9 m/s
- Answer: 9.9 m/s
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- A ball is dropped from a height of 2 m. Ignoring air resistance, how fast is it moving just before it hits the ground, in m/s? (g = 9.8 N/kg; give 1 decimal place) → 6.3 m/sPrompt: GPE lost = KE gained: m g h = ½ m v²
- A skateboarder leaves the bottom of a ramp at 7 m/s. Ignoring friction, what is the greatest height they can reach, in m? (g = 9.8 N/kg; give 2 decimal places) → 2.5 mPrompt: All the kinetic energy becomes gravitational potential energy.
You do: independent practice · 10 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 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- A ball is dropped from a height of 1 m. Ignoring air resistance, how fast is it moving just before it hits the ground, in m/s? (g = 9.8 N/kg; give 1 decimal place) → 4.4 m/sPrompt: GPE lost = KE gained: m g h = ½ m v²
- A 5 kg object falls 15 m. 10 % of its gravitational potential energy is transferred to the surroundings by air resistance. How much kinetic energy does it have at the bottom, in J? (g = 9.8 N/kg; give 1 decimal place) → 661.5 JPrompt: First find the GPE lost: m g h.
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: Kinetic and gravitational potential energy.
- Use concrete materials: wind-up toys or a pendulum.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- 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-10.
Free lesson plan from eurekami.com/lesson-plan-builder