U2C1

Vocabulary

Law of Conservation of Energy

Energy is neither created nor destroyed

When we use energy, it does NOT disappear

Energy transfers from object to object

A car engine burns gasoline, converting the chemical energy in gasoline into mechanical energy

Solar cells change radiant energy into electrical energy

Law of Conservation of Energy

EnergyEnergycauses interactionsability to do work or cause change

causes interactionsability to do work or cause change

Energy

Energy as Work

Potential Energy

•stored energy

Potential Energy

Potential Energy

potential energy

Kinetic Energy

•Energy in motion

kinetic energy

kinetic and potential energy

Energy SourceAn object that is the supplier of energy.

energy source

Energy Receiver

An object to which the energy is transferred.

energy receiver

Light

flashlight

Change in shape (pupil got smaller)

eye

Electric Circuit

cell

Change in illumination (light goes on/glows)

light bulb

energy transfers

Other Forms of Energy

•mechanical energy•thermal energy•chemical energy•electrical energy•electromagnetic energy•nuclear energy

Waves

waves, part 2

wavewave a continuous succession of pulses

wave

wave

wave

transverse wave a wave in which the motion of the material (medium) is perpendicular to motion of the wave

transverse wave

Motion Motion

Force Force

transverse wave

amplitude

the height of a wave crest. It is related to a wave’s energy

amplitude

amplitude

wavelength the distance between identical points along a wave

wavelength

frequency

the number of waves produced per unit time

frequency

Identify A?Identify B?

compression (longitudinal) wave

a wave in which the motion of the material (medium) is parallel to the motion of the wave

compression (longitudinal) wave

Motion Motion

Force Force

compression (longitudinal) wave

Types of Mechanical Waves

pitch

the quality of a sound dependent mostly on the frequency of the sound wave

pitch

sound energy

sound waves

ultrasound

compression waves at much higher frequency that animals or humans can hear

ultrasound

fault

a fracture in rock, along which the rock masses have moved

fault

earthquake

a sudden motion or shaking of the earth

earthquake

P wave a seismic wave that involves motion in the direction in which it is traveling: it is the fastest of the seismic waves

(compression wave)

P wave

P wave

S wave a seismic wave that involves vibration perpendicular to the direction the wave is traveling: it arrives later than the P wave(transverse wave)

S wave

L wave a seismic wave that travels along the surface of the Earth: they are the last to arrive at a location

L wave

seismograph

an instrument that detects seismic waves

seismograph

tsunami

a great sea wave produced by an earthquake (or volcanic eruption) on the ocean floor

wave interference

light waves

wave quiz

mechanical energythe energy transfer involved in an interaction that causes one or both objects to change position

push or pull applied an object

mechanical energy

forms of energy

constant speed

neither speeding up nor slowing down

constant speed

linear relationship

the relationship between two quantities that, when plotted against each other on a graph, produce a straight line

linear relationship

linear relationship

slopethe tilt or slant of a straight line on a graph: the rise divided by the run

slope

speeddistance traveled per unit timeexample: 55 mph

speed

speed = distance time

s = d t

speed

d

s t

average speed

the distance traveled divided by the time taken

average speed

average speed = total distance total time

average speed

nonlinear relationship

the relationship between two quantities that, when plotted against each other on a graph, do not produce a straight line

nonlinear relationship

nonlinear relationship

velocity•how fast an object is moving in a given direction•speed and direction

velocity

East at 750 mph

accelerationthe change in velocity per unit time

accelerationa = change in v time

a=(final v - initial v) time

fit(f-i)t

acceleration