Energy and Waves

• Energy is the ability to do work
• Work is a force causing movement of an object
• The unit of energy is joules
• Light is kinetic energy
• Electrical is kinetic energy
• Heat is kinetic energy
• Sound is kinetic energy
• Elastic is potential energy
• Gravitational is potential energy
• Nuclear is potential energy
• Chemical is potential energy
• Energy transfer is when energy is passed from one object to another in the same form
• Energy transformation is when energy is passed from one object to another in different form
• Input energy is the energy you start off with
• Output energy is the energy you end up with
• The law of conservation of energy states that energy can never be created nor destroyed
• Energy efficiency is how much energy you save
• To calculate energy efficiency divide the useful energy output by the energy input.
• Conduction is the transfer of heat energy between objects that are in contact
• Conduction happens between solids.
• Convection is the transfer of heat energy of a heated fluid such as water
• Radiation is energy that comes from a heat source that travels through space
• Independent variable is something that you as an experimenter changes
• Dependent variable is what gets measured in the experiment
• Controlled variables are things that stay the same to make the experiment fair
• Waves are the transfer of energy from one place to another without an object moving.
• Wavelength is the distance between two peaks (crest or trough)
• Amplitude is the measurement of the wave height from the middle (origin)
• Frequency is the number of waves per second
• Crest is the highest peak
• Trough is the lowest peak
• Mechanical waves need a medium to travel through
• Electromagnetic waves can travel in a space without matter
• Transverse waves happen when particles move at right angles to the wave direction.
• Longitudinal waves happen when particles move in the same direction as the wave
• Electromagnetic waves travel as transverse waves
• The incident ray is the (uninterrupted) ray that hits the surface
• The normal is the angle perpendicular to the surface
• The reflected ray is the ray that's reflected.
• Radiowaves is the first on the EMR spectrum