TalentJR apps
You need: a 30 cm ruler, a round pencil as the fulcrum, coins of one kind and a flat table. What happens: 2 coins 6 cm from the pencil balance 3 coins 4 cm from it on the other side. Why: a lever turns about its fulcrum, and each side’s turning effect is coins × distance. When both sides are equal, it balances (2 × 6 = 3 × 4 = 12). That is why a light child sits farther from the middle of a see-saw, and why a spoon handle opens a tin lid easily.
✓ You passed this lesson’s test.
Coins × distance — “a lever balances when coins × distance is equal on both sides of the fulcrum”
Use it for: Class 6–9 lessons on simple machines and moments; a STEM project for kids with coins.
Check: 3 coins × 4 cm = 2 coins × 6 cm = 12 ✓
▶ Watch it animatedWork it out in your head or on paper, type the answer and press Check. Stuck? Press “Show me how”.
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20 questions. Check each answer, then go to the next one. Get 16 or more right to pass.
🏅 Sign in with Google to earn the ⚖️ Lever Lifter badge when you pass — and a certificate when you finish all 10 lessons of Part 3 · Physics and STEM projects. You can still take the test without signing in.
Why does it work? When should you use it? Ask in English, मराठी or हिंदी.
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