The Laws That Run the Universe
📖 The Laws That Run the Universe
Newton's three laws of motion: 1st Law (Inertia): an object stays at rest or moves at constant velocity unless a resultant force acts on it. 2nd Law (F = ma): the resultant force on an object equals its mass multiplied by its acceleration — double the force, double the acceleration; double the mass, half the accelerati
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🧠 Memory Aid
The Three Laws as a Story:
Law 1 — "Stay Lazy": Objects are lazy — they stay as they are (rest or constant motion) unless a force makes them change. Inertia is physics laziness!
Law 2 — "F = ma": Force equals Mass times Acceleration. Remember the triangle: F on top, m and a on the bottom. Cover the one you want to find.
Law 3 — "Bouncer Rule": Every force gets a matching force back, on the OTHER object. Like a bouncer pushing you out — you push back on the bouncer with equal force, but on a DIFFERENT object.
Third Law pairs checklist — DOSE: Different objects, Opposite directions, Same magnitude, Equal type of force.
Now try it yourself
Quiz · Question 1 of 24
According to Newton's First Law, what happens to an object when there is no resultant force acting on it?
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This topic in real past papers
Every real exam question we've found on newton's laws of motion, with a full worked answer.