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Flashcards in Science Keys (Vocab) Deck (70):
1

Water Displacement

the method used to determine the volume of an irregular solid

2

Composition

what a substance is made of

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Temperature

the average kinetic energy of the molecules in matter

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Kinetic Energy

the energy of motion

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Density

the mass per unit volume of a substance (d = m/v)

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Volume

the amount of space taken up by an object

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Mass

the amount of matter in an object

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Weight

a measure of the force of gravity on an object

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The Scientific Method

an organized way of doing a science experiment

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Independent Variable

the one factor that is different in an experiment. it's what you are testing

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Dependent Variable

the result caused by the indepent variable. it's what you record as you do the experiment

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Constants / Controlled Variables

the things that stay the same as you do the experiment

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Speed

the rate of change in motion

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Velocity

speed in a direction

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Force

a push or pull exerted by one object on another object

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Balanced Forces

forces that do not cause a change in motion. the net force is 0 Newtons

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Unbalanced Forces

forces that always change the motion of an object

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Gravity

a force of attraction between objects because of their masses

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Friction

the force that opposes motion between 2 surfaces that are touching

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Air Resistance

the force that opposes motion or objects moving through air

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Newton's 1st Law of Motion

an object in motion will stay in motion, and an object at rest will stay at rest, until acted upon by an outside and unbalanced force

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Newton's 2nd Law of Motion

a force exerted on an object causes the object to accelerate in the direction of the force. the acceleration is affected by the mass of the object & the size of the force

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Newton's 3rd Law of Motion

for every action there is an equal and opposite reaction

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Work

when a force causes an object to move in the direction of the force

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Energy

the ability to do work

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Potential Energy

stored energy and the energy because of position

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Mechanical Energy

the total energy of motion and position

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Energy Conversion

a change from one form of energy to another

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Law of Conservation of Energy

states that energy cannot be created or destroyed

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Closed System

a group of objects that only transfer energy to themselves

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Renewable Resources

resources that can be replenished naturally in a short period of time

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Nonrenewable Resources

resources that cannot be made again in a short period of time

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Simple Machines

a machine with few or no moving parts; a device that makes work easier by changing the size or direction of the force

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Mechanical Advantage

the benefit gained by using machines; the number of times the machine multiplies the force

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Fulcrum

the point on a lever where it pivots

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Work Input

the work done on a machine - caused by the input force

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Work Output

the work a machine does - caused by the output force

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Compound Machine

2 or more simple machines working together

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Physical Properties

a property of matter that can be observed or measured without changing the identity of the matter

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Chemical Properties

the property of matter that describes its ability to change into new substances with different properties

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Physical Changes

a change from one form to another that affects one or more physical properties

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Chemical Changes

a change that occurs when one or more substances change into new substances with different properties

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States/Phases of Matter

matter exists in 4 different states/phases: solid, liquid, gas, & plasma

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Melting

when a solid changes to a liquid; energy is added

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Freezing

when a liquid changes to a solid; energy is removed

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Condensation

when a gas changes to a liquid; energy is removed

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Evaporation

when a liquid changes to a gas; energy is added

48

Crust

the outermost layer of the Earth.
Continental crust - composition is similar to granite; the avg. thickness is 30km.
Oceanic crust - composition is similar to basalt; is 5-8km thick; is denser than continental crust

49

MOHO

the boundary between the crust & the mantle

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Mantle

the layer of the Earth between the crust & the core; extremely thick; contains most of the Earth's mass

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Outer Core

the liquid layer of the Earth's core; lies beneth the mantle; surrounds the inner core

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Inner Core

the solid, dense center of the Earth that extends from the bottom of te outer core to the center of the Earth; 6,378km beneath the surface

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Plasticity

the propert in which a solid can flow slowly like a thick liquid

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Lithosphere

the outermost, rigid layer of the Earth; made of 2 parts: the crust & the rigid upper part of the mantle; divided into pieces called tectonic plates

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Asthenosphere

the soft layer of the mantle on which pieces of the lithosphere move; made of solid rock that flows very slowly

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Mesosphere

beneath the asthenosphere; strong, lower part of the mantle; extends from the bottom of the asthenosphere down to the Earth's core

57

Continental Drift

the theory that 1) continents can drift apart & have done so in the past, & 2) all present continents were once connected into a super continent called Pangaea

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Plate Tectonics

the theory that the earth's lithospere is divided into tectonic plates that move around on top of the asthenosphere

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Convergent Boundary

the boundary where 2 tectonic plates that are pushing into each other meet

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Divergent Boundary

the boundary between where 2 tectonic plates are moving away from one another

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Transform Boundary

the boundary between 2 tectonic plates that are sliding past each other horizontally

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Seafloor Spreading

the process by which new oceanic lithosphere is created as older materials are pulled away from the ridge (as tectonic plates move away from each other, the seafloor spreads apart & magma rises to fill in the gap)

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Subduction Zone

the region where an oceanic plate sinks down, beneath either a continental plate or a less dense oceanic plate, into the lithosphere at a convergent boundary

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Folding

the bending of rock layers due to stress in the Earth's crust

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Fault

a break in the Earth's crust along which blocks of the crust slide relative to one another due to tectonic forces

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Normal Fault

a fault in which the hanging wall moves down relative to the footwall.

usually occurs when rocks are pulled apart due to tension

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Reverse Fault

a fault in which the hanging wall moves up relative to the footwall.

usually occurs when rocks are pushed together by compression

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Strike-Slip Fault

a fault in which the 2 fault blocks move past each other horizontally.

the fractures are vertical or nearly vertical

69

Hot Spot

a place on the Earth's surface that is directly above a column of risin magma called a mantle plume

70

Ring of Fire

the plate boundaries surrounding the Pacific Ocean have so man volcanoes that these boundaries together are called the Ring of Fire