Physics Notes on Speed, Density, and Work Formulas

Essential Physics Formulae

Speed = Distance ÷ Time is probably the most useful formula you'll learn this year. Whether you're calculating how fast a car travels or how quickly sound moves through air, this equation has you sorted. Remember that speed is measured in metres per second (m/s) or kilometres per hour (km/h).

Density = Mass ÷ Volume tells you how tightly packed the particles in a material are. A dense material like lead has lots of mass crammed into a small space, whilst something less dense like cork has the same mass spread out over a larger volume. Density is typically measured in grams per cubic centimetre $g/cm³$.

Work = Force × Distance calculates the energy transferred when you apply a force to move something. Push a heavy box across the room? You're doing work! The harder you push (more force) and the further you move it (more distance), the more work you've done.

Quick Tip: Practice rearranging these formulae to find any missing value - it's a common exam trick that catches students out!