science final review notes. does it float or sink?

Science Final Review Notes

Does it Float or Sink?

Density is less than 1.0 g/cm3

Density is more than 1.0 g/cm3

FLOATS

SINKS

Solids

• Phase of matter in which matter has a definite shape and volume

Molecules (small round objects)

are arranged and organized in

“tightly packed” order

Liquids

• Phase of matter in which matter takes the shape of its container and has

definite volume

Molecules are moving slowly; not fast enough to overcome the

attractions between them

Gases

• Phase in which matter changes in both volume and shape

Molecules move very quickly and are able to break apart from one

another

So How Do We Classify Them?

• How fast the molecules move!!!

Solids Liquids Gases Plasmas

Molecules move slow and vibrate

in place

Move faster than solids and overcome

some attraction

Move fast and

overcome all of

attraction

Move incredibly fast but

break apart

• Potential Energy – Stored energy

• Kinetic Energy – Energy of motion

Circuits

• Complete, closed path through which electric charges flow

Closed Open

Two Types of Circuits

• 1. Series: all parts are connected in one loop

Types Of Circuits

• 2. Parallel: different loads are located on separate branches

Types Of Waves

• 2 Types

1. Transverse Waves

2. Longitudinal Waves

These two waves can be identified by the direction in which the particles of the

medium vibrate compared with the direction in which the waves travel

Transverse Waves

• Transverse: waves that move across

Particles in a transverse wave move across or perpendicular to the direction of the wave

Longitudinal Waves• Longitudinal: the particles of a medium

vibrate back and forth along the path that the wave travels

Properties of Waves

• Amplitude: the maximum distance the wave vibrates from its rest position

Larger the amplitude = taller wave

What Does Amplitude Mean?

• Small Amplitude = low energy

• Large Amplitude = high energy

Wavelength• Wavelength: the distance between

any two adjacent crests or compressions

Frequency

• Frequency: the number of waves produced in a given amount of time

Expressed in Hertz

Newton’s Laws

1. An object in motion tends to stay in motion unless acted upon by an outside force

2. Force = mass x acceleration

3. For every action, there is an equal and opposite reaction

• The seven types of energy are:

Energy

Heat

Light

Electrical

MechanicalSound

Nuclear

Chemical

What Makes An Object Move?• Force: a push or pull on an object

Characteristics of Forces

1. Have size

2. Direction

40.0 Newtons

3. Units = Newtons

Law of Gravity

• What goes up must come down.

• Gravitational force increases with increased mass of the object or decreased distance between objects.

Law of Conservation of Energy

• Energy cannot be created or destroyed. Energy can only change form.

Levers

• A simple machine consisting of a bar that pivots at a fixed point

Fulcrum: pivot point

Inclined Planes

• Simple machine that is a straight, slanted surface

The longer an inclined plane is compared to its height, the greater the mechanical

advantage

Wheel and Axle

• Consists of two circular objects of different sizes

The wheel allows the individual to spin the axle easier

1st Circular Object

2nd Circular Object

Pulleys

• Consists of a grooved wheel that holds a rope or a cable

Compound Machines

• Machines that are made of two or more simple machines

The more moving parts, the more mechanical advantage

What is Friction Then?o Friction: a force that

opposes motion between two surfaces that are touching

There is NO SUCH THING as a

completely smooth surface!!

Efficiency In Machine

• Machines can be made to be more efficient

We do this by REDUCING…

Lubricants: substances that are applied to surfaces to reduce friction between them

Physical Properties

Can be observed without changing what the object originally was

EXAMPLES OF PHYSICAL PROPERTIES

Hair

Chalk

Apple

Water

Color Shape ColorTaste

Color Texture Liquid Clear

Physical Changes

Changes in size, shape, or color (the object is still the same substance)

EXAMPLES OF PHYSICAL CHANGES

Hair

Chalk

Apple

Water

HAIRCUT STILL HAIR! SLICEDSTILL AN APPLE!

BREAK STILL CHALK!COLORING

STILL WATER!

Chemical Changes

Evident when we make a NEW SUBSTANCE!!

EVIDENCE OF PHYSICAL/CHEMICAL CHANGES

PHYSICAL CHANGES CHEMCIAL CHANGES

Size Bubbling

Shape Flammable

Color Dissolving/Dissolves

Solubility Curves

** A WAY TO FIGURE OUT HOW MUCH

SUBSTANCEYOU CAN DISSOLVE AT

DIFFERENT TEMPERATURES**** Match the

temperature at the bottom with the grams

of solute on the left side…where they meet is the solubility for that

substance**

Electromagnetic Spectrum

• Name for the range of electromagnetic waves when they are placed in order of

increasing frequency

Electromagnetic Spectrum Continued

long Wavelength short

low Frequency high

Refraction Bending of a wave as it passes at an

angle from one medium to another

Reflection

Allows us to see objects that do not produce their own light

When light or any other waves bounces off an object

Absorption and Scattering

Absorption: the transfer of energy carried by light waves to particles of matter

Light and Color Color is produced by REFLECTION

and ABSORPTION!!!!

The colors that are REFLECTED are the colors that you can see!!!!!!

What Are Our Basic Colors?

THE RAINBOW!!!Meet ROY G. BIV

ROYGBIV

= RED= ORANGE= YELLOW= GREEN= BLUE= INDIGO= VIOLET