Science Keys (Vocab) Flashcards
Water Displacement
the method used to determine the volume of an irregular solid
Composition
what a substance is made of
Temperature
the average kinetic energy of the molecules in matter
Kinetic Energy
the energy of motion
Density
the mass per unit volume of a substance (d = m/v)
Volume
the amount of space taken up by an object
Mass
the amount of matter in an object
Weight
a measure of the force of gravity on an object
The Scientific Method
an organized way of doing a science experiment
Independent Variable
the one factor that is different in an experiment. it’s what you are testing
Dependent Variable
the result caused by the indepent variable. it’s what you record as you do the experiment
Constants / Controlled Variables
the things that stay the same as you do the experiment
Speed
the rate of change in motion
Velocity
speed in a direction
Force
a push or pull exerted by one object on another object
Balanced Forces
forces that do not cause a change in motion. the net force is 0 Newtons
Unbalanced Forces
forces that always change the motion of an object
Gravity
a force of attraction between objects because of their masses
Friction
the force that opposes motion between 2 surfaces that are touching
Air Resistance
the force that opposes motion or objects moving through air
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
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
Newton’s 3rd Law of Motion
for every action there is an equal and opposite reaction
Work
when a force causes an object to move in the direction of the force
Energy
the ability to do work
Potential Energy
stored energy and the energy because of position
Mechanical Energy
the total energy of motion and position
Energy Conversion
a change from one form of energy to another
Law of Conservation of Energy
states that energy cannot be created or destroyed
Closed System
a group of objects that only transfer energy to themselves
Renewable Resources
resources that can be replenished naturally in a short period of time
Nonrenewable Resources
resources that cannot be made again in a short period of time
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
Mechanical Advantage
the benefit gained by using machines; the number of times the machine multiplies the force
Fulcrum
the point on a lever where it pivots
Work Input
the work done on a machine - caused by the input force
Work Output
the work a machine does - caused by the output force
Compound Machine
2 or more simple machines working together
Physical Properties
a property of matter that can be observed or measured without changing the identity of the matter
Chemical Properties
the property of matter that describes its ability to change into new substances with different properties
Physical Changes
a change from one form to another that affects one or more physical properties
Chemical Changes
a change that occurs when one or more substances change into new substances with different properties
States/Phases of Matter
matter exists in 4 different states/phases: solid, liquid, gas, & plasma
Melting
when a solid changes to a liquid; energy is added
Freezing
when a liquid changes to a solid; energy is removed
Condensation
when a gas changes to a liquid; energy is removed
Evaporation
when a liquid changes to a gas; energy is added
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
MOHO
the boundary between the crust & the mantle
Mantle
the layer of the Earth between the crust & the core; extremely thick; contains most of the Earth’s mass
Outer Core
the liquid layer of the Earth’s core; lies beneth the mantle; surrounds the inner core
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
Plasticity
the propert in which a solid can flow slowly like a thick liquid
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
Asthenosphere
the soft layer of the mantle on which pieces of the lithosphere move; made of solid rock that flows very slowly
Mesosphere
beneath the asthenosphere; strong, lower part of the mantle; extends from the bottom of the asthenosphere down to the Earth’s core
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
Plate Tectonics
the theory that the earth’s lithospere is divided into tectonic plates that move around on top of the asthenosphere
Convergent Boundary
the boundary where 2 tectonic plates that are pushing into each other meet
Divergent Boundary
the boundary between where 2 tectonic plates are moving away from one another
Transform Boundary
the boundary between 2 tectonic plates that are sliding past each other horizontally
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)
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
Folding
the bending of rock layers due to stress in the Earth’s crust
Fault
a break in the Earth’s crust along which blocks of the crust slide relative to one another due to tectonic forces
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
Reverse Fault
a fault in which the hanging wall moves up relative to the footwall.
usually occurs when rocks are pushed together by compression
Strike-Slip Fault
a fault in which the 2 fault blocks move past each other horizontally.
the fractures are vertical or nearly vertical
Hot Spot
a place on the Earth’s surface that is directly above a column of risin magma called a mantle plume
Ring of Fire
the plate boundaries surrounding the Pacific Ocean have so man volcanoes that these boundaries together are called the Ring of Fire
