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Updated Mar 20, 2026

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The Basics of Physics

hotline_bling

@hotline_bling

Physics mechanics explores how objects move and respond to forces.... Show more

# Physics mechanis

vector quantities → have a size and direction

beg. weight, displacement, forces

scalar quantities

Leg. mass, spee

Forces and Motion in Physics

Everything in mechanics can be classified as either vector quantities (having both size and direction) like weight and forces, or scalar quantities (having only size) like mass and time. This distinction is crucial when solving physics problems.

Forces change how objects move by altering their speed or direction. Measured in newtons (N), they're represented as arrows on diagrams, with the arrow length showing strength and direction. Newton's laws explain how forces work: the 1st law states objects stay at rest or in constant motion unless a force acts on them; the 2nd law shows acceleration depends on force and mass; while the 3rd law tells us every action has an equal and opposite reaction.

When objects collide, different things can happen. In elastic collisions, both momentum and energy are conserved. Partially inelastic collisions lose some kinetic energy but objects separate, while in totally inelastic collisions objects stick together afterward.

Quick Tip: When drawing force diagrams, make sure the length of your arrows is proportional to the force strength - this visual representation helps you understand which forces dominate in a system.

Materials respond differently to forces. Hooke's Law states that a material's extension is proportional to the applied force up to its elastic limit. Brittle materials like glass follow this law until they break suddenly, while ductile materials stretch beyond their elastic limit before breaking. Rubber materials don't follow Hooke's Law at all because of their unique chemical properties.

In circular motion, an object may have constant speed but its direction constantly changes. This change in direction means there's acceleration toward the center, requiring a centripetal force that keeps the object moving in a circle rather than flying off in a straight line.

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Updated Mar 20, 2026

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1 page

The Basics of Physics

hotline_bling

@hotline_bling

Physics mechanics explores how objects move and respond to forces. It's a fundamental area of physics where we learn about forces, motion, collisions, and materials - concepts that explain everything from why cars stop when you brake to how buildings... Show more

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Forces and Motion in Physics

Quick Tip: When drawing force diagrams, make sure the length of your arrows is proportional to the force strength - this visual representation helps you understand which forces dominate in a system.