Three laws that explain how the universe moves — all animated
Newton published Principia Mathematica in 1687, containing his famous three laws that form the foundation of classical mechanics.
An object at rest stays at rest, and an object in motion stays in motion, unless acted upon by an external unbalanced force.
The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.
For every action, there is an equal and opposite reaction. Forces always occur in pairs.
Watch the same force applied to different masses — lighter object accelerates more!
When a car stops suddenly, you lurch forward — your body wants to stay in motion (inertia). Seatbelts apply external force to stop you.
A heavier ball needs more force to achieve the same acceleration. Bowlers put more force into bowling a heavier ball harder.
Rocket exhaust gases pushed backward → reaction force pushes rocket forward!
You push the ground backward → ground pushes you forward!
Q: A force of 50 N acts on a body of mass 10 kg. What is the acceleration? If friction is 10 N, find net acceleration.
F = 50 N, m = 10 kg, friction f = 10 N
a = F/m = 50/10 = 5 m/s²
F_net = 50 − 10 = 40 N
a = F_net/m = 40/10 = 4 m/s²
Newton's Laws mastered! 🎉
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