Scalar and Vector Quantities
Think about giving directions to your mate - saying "walk 5 metres" isn't very helpful, but "walk 5 metres north" gets them where they need to go. That's the difference between scalar and vector quantities in physics.
Scalar quantities only have size (magnitude) - like distance, speed, mass, and temperature. You just need a number to describe them completely. Vector quantities need both size and direction - like displacement, velocity, acceleration, and force.
Forces are always vectors because they push or pull in specific directions. They come in two types: contact forces (like friction) where objects must touch, and non-contact forces (like gravity) that work across empty space. You can represent forces using arrows - longer arrows mean stronger forces, and the arrow points in the force's direction.
Quick tip: If you need to know "which way", it's probably a vector quantity!
