You will learn
- Define balanced forces.
- Explain no change in motion.
- Identify balanced pairs.
- Apply to real examples.
Version 0.2 · expanded edition · built from cited public sources Content is based on the official frameworks and sources listed under Sources and standards. No official endorsement is claimed. Written in the style of common primary school assessments. No exam result is promised.
Student lesson
Words to know
equal forces in opposite directions
the overall force on an object
a state with balanced forces
the upward push of a liquid
1. Discover: The tug-of-war draw
Two teams pull equally on a rope and the marker in the middle does not move. “The forces are balanced,” says Coach Osei. “The resultant force is zero.”
Think: What happens when one team pulls harder?
2. Understand: Balance
Idea 1: Equal and opposite
Balanced forces are equal in size and opposite in direction. The resultant force, the overall force, is zero.
Idea 2: Effect
With zero resultant force, a stationary object stays still and a moving object keeps the same speed in a straight line. This is the idea behind Newton’s first law.
Idea 3: Examples
A book on a table: weight down, support force up. A floating boat: weight down, upthrust up. A cyclist at steady speed: forward push equals friction and air resistance.
3. Worked examples
Example 1 (I show you): Identify
Balanced.
- Equal.
- Opposite.
- Zero resultant.
Answer: Balanced pair.
Example 2 (We do it together): Draw
Book on table.
- Weight down.
- Support up.
- Equal.
Answer: Two arrows.
Example 3 (You try): Explain
Floating.
Show the steps and answer
- Weight.
- Upthrust.
- Equal.
Answer: Balanced.
Did you know?
Spacecraft far from planets can coast with nearly no resultant force for years.
Why this matters
Balanced forces explain why structures stand and boats float.
4. Explore: Floating test
Float a small plastic boat in water and add coins until just before it sinks; draw its forces at each stage.
- Float the boat.
- Add coins.
- Record coins.
- Draw forces.
Think about it: what did you notice?
What did you notice? The boat floated while upthrust matched the weight.
5. Practise
Say it in a sentence
Use these starters when you talk about the lesson. Say them out loud.
- ___ forces are equal and opposite.
- The ___ force is the overall force.
- ___ is a state with balanced forces.
- ___ is the upward push of a liquid.
Guided practice
Question 1. What are balanced forces?
Equal, opposite.
Question 2. What is the resultant?
Overall force.
Question 3. What is upthrust?
Upward push.
Independent practice
Level 1: Start
- What are balanced forces?
- What is the resultant?
- What is upthrust?
- What is equilibrium?
- What is zero resultant?
Level 2: Grow
- Why no movement?
- Why floats?
- Why steady speed?
Level 3: Stretch
- Float the boat.
- Draw arrows.
- Explain.
Answers are in the answer key below. Try first, then check.
6. Apply: Science in everyday life
Explain why a book on a table does not move.
Show a sample answer
Use forces.
Another one. Tell a family member one thing from this lesson. Use the words you learned.
Show a sample answer
A clear sentence that uses at least one word from Words to know.
7. Common mistakes
Fix: Balanced forces.
Fix: Not at steady speed.
8. Lesson summary and revision card
- I can define balanced forces.
- I can explain no change in motion.
- I can identify balanced pairs.
- I can apply to real examples.
9. Check and master
Answer all 14 questions. You will see feedback after each one.
Your result appears here after you answer every question.
10. Key takeaways
- Balanced forces have a resultant of zero.
- Zero resultant means no change in motion.
- A book on a table has gravity and support balanced.
- Floating means weight equals upthrust.
11. Next lesson
Next lesson: Unbalanced forces. Keep going with the next idea in this course.
Exam practice
These questions are written in the style of common school and international primary assessments. Try them on your own, without looking back. Then check your answers in the marking guide. The marks are shown in brackets.
- Define balanced forces and resultant force. [2 marks]
- Draw and label forces on a book at rest. [3 marks]
- Explain floating. [3 marks]
- Safety rule. [2 marks]
Total: 10 marks.
Marking guide and model answers
- 1 each
- Weight [1]; support [1]; equal [1]
- Weight down [1]; upthrust up [1]; equal [1]
- Any [1]; reason [1]
Score guide: 9 to 10 = secure. 6 to 8 = nearly there, revise the parts you missed. Under 6 = work through the lesson again with a grown-up.
Printable worksheet
- What are balanced forces?
- What is the resultant?
- What is upthrust?
- What is equilibrium?
- What is zero resultant?
- Why no movement?
- Why floats?
- Why steady speed?
- Float the boat.
- Draw arrows.
Homework
Find three objects at rest at home and draw their forces.
Answer key and marking scheme
| Question | Expected response | Marks |
|---|---|---|
| 1. What are balanced forces? | Equal, opposite. | 1 |
| 2. What is the resultant? | Overall force. | 1 |
| 3. What is upthrust? | Upward push. | 1 |
| 4. What is equilibrium? | Balanced state. | 1 |
| 5. What is zero resultant? | No change. | 1 |
| 6. Why no movement? | Balanced. | 1 |
| 7. Why floats? | Upthrust equals weight. | 1 |
| 8. Why steady speed? | Balanced. | 1 |
| 9. Float the boat. | Table. | 1 |
| 10. Draw arrows. | Diagram. | 1 |
| Total | 10 |
Independent practice answers. Level 1: 1 Equal, opposite.; 2 Overall force.; 3 Upward push.; 4 Balanced state.; 5 No change.. Level 2: 1 Balanced.; 2 Upthrust equals weight.; 3 Balanced.. Level 3: 1 Table.; 2 Diagram.; 3 Sentence..
Quiz answers: 1 B, 2 C, 3 A, 4 B, 5 C, 6 A, 7 B, 8 C, 9 A, 10 B, 11 C, 12 A, Challenge 1 B, Challenge 2 C.
Mastery and remediation
| Objective | Bronze (Developing) | Silver (Proficient) | Gold (Advanced) |
|---|---|---|---|
| O1 Define balanced forces | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O2 Explain no change in motion | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O3 Identify balanced pairs | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
| O4 Apply to real examples | Shows this with help from an adult or a picture | Does this independently and explains how they know | Explains it clearly and uses it in a new situation |
Courseversity badge thresholds (overall quiz score): Gold = 90–100%; Silver = 80–89.9%; Bronze = 70–79.9%. A badge is never a full record of progress.
If a learner struggles
- Find the misconception: “No movement means no forces.” Balanced forces.
- Explain another way: use real objects, pictures or actions first, then words.
- Show a simpler example: Explain balanced forces.
- Guided practice: work through one example together and let the learner try the next one.
- Reassess: use the quiz again or the worksheet.
- Move on when the learner shows Silver-level evidence independently.
For parents and guardians
In this lesson your child studies balanced forces. You do not need to be an expert to help.
- Float a toy.
- Ask “What holds it up?”
- Mind spills.
- Ask “how do you know?” after each answer, and listen.
- Praise effort, not only right answers. Mistakes are how we learn.
- Ten to fifteen minutes a day is better than one long session.
Teacher package
1–5. Objectives, prerequisites, materials, preparation, duration
Lesson objectives. Learners will: define balanced forces; explain no change in motion; identify balanced pairs; apply to real examples.
Prerequisite knowledge. Grade 5 ideas: pushes, pulls, gravity, friction and air resistance.
Materials. Plastic container, water, coins, tray. Low-resource options: use chalk or charcoal on a board or wall, drawings in the sand, and objects from the classroom instead of printed materials.
Preparation. Fill containers.
Suggested duration. 45–60 minutes. It can be split into two shorter sessions.
6–9. Teaching procedure, explanation notes, guided and independent activities
Introduction (5 min). Balance a book on a hand and ask, “Why does it not fall?”
Explanation (10 min). Teach balance.
Guided activity (10 min). Learners test.
Independent activity (10 min). Learners draw.
Assessment and reflection (5 min). Ask each learner to say one thing they learned and how they know it.
Key questions. Which forces? Are they equal?
Teacher explanation notes. Start with real objects and safe, hands-on observation. Then talk about what was seen, then draw and write. Always say “how do you know?”. Keep to the safety notes, and use local, safe materials.
10–12. Differentiation, formative assessment, common misconceptions
Support. Use real objects and pictures, short sentences and a partner. Let learners point, show or draw instead of writing. Extension. Ask learners to find a new example at home and explain how they know.
Formative assessment. Listen to learners read and explain, ask “how do you know?”, and check the independent work.
Misconceptions. “No movement means no forces.” Balanced forces.
13–15. Assessment questions, answer keys, marking scheme
Use the quiz, the 10-mark exam practice and the worksheet on this page. All answers and marking guides are in the answer sections above. Re-check every answer before use.
16–19. Remediation, enrichment, homework, teacher reflection
Remediation. Explain balanced forces. Enrichment. Look for one new example near your home or school, draw it and explain it to someone. Homework. See above.
Teacher reflection. After teaching, record: which ideas learners understood; which misconceptions occurred; which activities worked; which learners need more practice; and what to improve next time.
Sources and standards
This lesson is based on the sources below, and no official endorsement is claimed. Reference starting points: Next Generation Science Standards, Cambridge Primary Science and the IB Primary Years Programme. Where a standard code is named, it points to the official framework.
Research used to shape this lesson. Courseversity Science curriculum, Grade 6 Unit 6, topic 2; Next Generation Science Standards, forces and interactions; Cambridge Lower Secondary Science, physics; IB Primary Years Programme, how the world works. These sources informed the lesson.