Chapter 3 Study guide Gravity: • • • • • Definition What affects gravity How air resistance and surface area affect the force of gravity What happens to objects when dropped in a vacuum (no air) Free fall means the object is weightless so the force of gravity would be equal on the object and Earth. Weight: • Definition • Units used to measure weight • Can it change? Mass: • • • • Definition Tool used to measure mass Units used to measure mass Can it change? Friction: • Definition • Know the 4 types and what they are (be able to identify by examples) • Know that friction produces heat Pressure: • Know what happens to pressure below and above sea level (does it increase? decrease?) • Units used to measure pressure • Formula for pressure Buoyancy: • Definition • Bernoulli’s Principle (what is states and examples) • Pascal’s Principle (what it states and examples) Density: • Formula • Units • What happens when an object is placed in a substance that is more dense and less dense?