Summary

This document is a G4 science review sheet, summarizing key concepts in physics, including forces, motion, energy, heat, sound, and light. It covers topics like velocity, acceleration, and different types of energy.

Full Transcript

G4 Review Sheet C11 L1: Forces and Motion Position is the location of an object Motion is movement that changes an objects position Speed is the distance moved in an amount of time Velocity is the speed and direction of a moving object Inertia is the tendency of an object in motion t...

G4 Review Sheet C11 L1: Forces and Motion Position is the location of an object Motion is movement that changes an objects position Speed is the distance moved in an amount of time Velocity is the speed and direction of a moving object Inertia is the tendency of an object in motion to stay in motion or an object at rest to stay in rest A force is a push or pull Acceleration is a change in speed of an object Friction is the force that works against motion Gravity is the force that pulls objects down toward Earth C11 L2: Changing Motion Newton - the unit we use to measure force Balanced forces - forces that are equal in size with opposite directions Unbalanced forces- forces that are not equal in size with opposite directions When mass increases, acceleration decreases When force increases, acceleration increases Balanced Force Unbalanced Force C11 L3: Work and Energy Work is done when force is used to move an object a distance Energy is the ability to do work Potential energy is stored energy Kinetic energy is the energy of motion (movement) Energy can be transferred - moved from one object to another (if you roll a marble to hit another marble the kinetic energy transfers to the second marble) Energy can be transformed - changed from one form to another (if you switch on a blender it transforms electrical energy to mechanical energy) C11 L3: Work and Energy Different types of energy ○ Chemical energy - food, batteries ○ Light energy - sunlight ○ Thermal energy - fire, heat ○ Electrical energy - electricity ○ Mechanical energy - energy in motion (both potential and kinetic) ○ Nuclear energy - energy that comes from tiny particles of matter C12 L1: Heat Heat is the flow of thermal energy from one object to another Temperature measures the thermal energy of the particles in a substance We measure temperature with a thermometer. Thermometers have liquid mercury inside them. Conduction - heat transfer between two objects that are touching Convection - heat transfer through liquids or gases Radiation - heat transfer through space (no matter is needed) A material that does not transfer heat energy easily is an Insulator (cotton, plastic) A material that transfers heat energy easily is a conductor (metal) C12 L2: Sound Sound travels in ○ Solid - fastest speed ○ Liquid - second fastest speed ○ Gas - slowest speed Sound cannot travel through outer space since there is no matter in space Wavelength - the distance between waves Frequency - the number of vibrations sound makes, it affects Pitch Pitch - the highness or lowness of sound Amplitude - the amount of energy in a sound wave, it affects volume Volume - the loudness of a sound C12 L3: Light Light travels in waves Transparent materials allow light to pass through (glass) Translucent materials scatter light in different directions Opaque materials block light completely Colors of visible light: ○ Red, Orange, Yellow, Green, Blue, Indigo, Violet ○ ROYGBIV Red has the longest wavelength, Violet has the shortest wavelength C12 L3: Light Reflection is when light waves bounce off a surface Refraction is when light rays bend when it moves from one material to another C12 L4: Electricity Electrical charges can be negative or positive When a lot of charges build up (are collected), its known as static electricity A circuit is a path where electric current flows The flow of electrical charges through a circuit is called electric current Electrical conductors are the same as heat conductors (metal) + And - charges attract each other - And - charges repel each other + And + charges repel each other Circuit C12 L4: Electricity Fuses can only be used one time. The wire in the fuse melts when there is too much electricity/ heat and then breaks the connection. Circuit breakers can be used many times. The switch switches off when there is too much electricity/ heat and then breaks the connection. Fuses and circuit breakers prevent your TV/ fridge from burning with the extra electricity.

Use Quizgecko on...
Browser
Browser