Turning Effect of Forces
Why a door handle is far from the hinge, and how a see-saw balances.
What this lesson covers
Turning Effect of Forces is a 8-part Class 9 Physics lesson. Each part makes one point and then hands over to the next, so it can be read in a sitting or picked up again at the part you stopped on. It defines the idea in plain words before using it, works through an example step by step, breaks the topic into its parts and compares them, shows where it is used outside the textbook, names the mistakes that cost marks in an exam, ends with a recap of what to remember.
How it begins
Push a door near its hinge and almost nothing happens. Push the same amount at the handle and it swings open. The force is identical. What changed is the distance from the pivot. The turning effect of a force is called its moment: moment = force × perpendicular distance from the pivotMeasured in newton metres (N m). "Perpendicular" matters: only the part of the distance at right angles to the force counts.
The 8 parts
- What a moment is
- The principle of moments
- Centre of mass and stability
- A balance problem
- Levers everywhere
- Where marks get lost
- What to remember
- Watch one worked through
Practise Turning Effect of Forces
Everything on QuizByt for Class 9 Physics that goes with this lesson: read it first, then test yourself while it is fresh.
🧠 5 quizzes on Turning Effect of Forces (2 easy, 2 medium, 1 hard)
Work up from easy to hard: the hard quiz asks the Class 9 exam-style questions on Turning Effect of Forces.
🖨️ Printable worksheet
Turning Effect of Forces on paper for Class 9, with room to write the working out. Preview the first page free.
🎮 Games for Class 9 Physics
Memory and reasoning games at the right level for Class 9. Passing a quiz on Turning Effect of Forces earns the credits that open them.
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