84 terms

# Investigating God's World - Chapter 6

#### Terms in this set (...)

Force
A push or pull
Gravity
The force of attraction that exists between any pair of objects
Matter
Anything that takes up space and has mass
Mass
The amount of matter
Weight
The measure of the gravitational force (downward pull) existing between the earth and a particular object

The more mass--the more gravitational pull--the more an object weighs.
Contact force
Force that occurs when one object pushes against another object
Friction
Force that resists motion
Why would you weigh less on the moon than on the earth?
Because the moon is much smaller than the earth, it's force of gravity is weaker than the earth's gravity. This means an object would weigh much less on the moon than on earth.
Why does an elephant weigh more than a mouse?
The more mass an object has, the greater the downward pull on it, therefore the more an object weighs.
Which force keeps you from floating into space?
Force of Gravity
Why can you not detect the force of attraction between your foot and the leg of your chair?
Because they aren't pushing against each other
What kind of force do you use when you beat a drum?
Force of Contact
What kind of force do you use when you use the brakes on a bicycle?
Force of Friction
What causes electrically charged objects to either attract of repel one another?
Electrical Force
Name the special rock used in the first compasses.
Lodestones (pieces of naturally magnetized iron ore)
How do like charges and like poles react to each other?
Like charges and like poles repel each other
How do opposite charges and opposite poles react to each other?
Opposite charges and opposite poles attract each other
What does every magnet have?
Every magnet has a north-seeking pole and a south-seeking pole
Energy
The ability to do work
Kinetic Energy
Energy of motion (flying bullet, speeding train, falling rock, bouncing ball, etc.)
Potential Energy
"Stored energy" because of its position (stretched rubber band, blown up balloon--holding end not letting air out, water behind a dam, tightly wound spring, car parked on a hill, etc.)
Engine
Devices that can convert energy from natural sources into useful work
Transfers of Energy
Occurs when one object gives some or all of its energy to another object
Work
The result of a force moving an object
Is work accomplished if you push hard on a wall? Why or why not?
No, because you didn't move anything
Name an item in which chemical energy is found.
Piece of wood, lump of coal, gallon of gas, slice of Apple pie. Energy stored in these things is released as heat energy through burning or some chemical process
Which is more reliable, wind or water power?
Water
In modern times, what sources of energy are used in place of wind pushing on sails to propel vessels?
Steam, diesel, nuclear
Water-powered mills were built near what?
Rivers
2 devices that man has developed to harness the power of the wind.
Windmill, wind turbine
What device has man developed to harness the power of running water?
Water wheel
Name two products that were manufactured with the help of water wheels
Power loom
Spinning jenny
Water frame
Flying shuttle
What were early textile factories called?
Mills
Substance changes from solid to liquid
Melting point
Substance changes from liquid to solid
Freezing point
Substance changes from liquid to gas
Boiling point
Substance changes from gas to liquid
Condensation point
Why are liquids and gases both called fluids?
Both contain water
Boiling point and condensing point of water
212
Give the melting and freezing point of water
32
What is water in a solid state called?
Ice
What is water in its gaseous state called?
Steam
What do molecules in the ice Crystal form?
Hexagons
Define furnace
Sometimes called a firebox, in which wood, coal, or oil is burned to produce heat
Define boiler
Changes the heat from burning fuel into steam in the engine
Piston
Disk that moves back and forth
Condenser
Old steam goes into the condenser where it is cooled and changed into water
Who patented his own improved version of the steam engine in 1769?
James Watt
What is combustion?
Another name for burning. If something is combustible, it means that it will burn. If something is noncombustible, it means that it will not burn.
What are the 2 ingredients for combustion?
Fuel and oxygen
What type of engine burns fuel INSIDE the engine?
INternal combustion engine
What type of combustion engine is the steam engine?
External Combustion Engine
The burning of fuel releases chemical (special form of potential energy) energy in what two forms?
Light and Heat energy
What does a gasoline's octane number indicate?
Ability to resist "knocking" sound in engine and to burn smoothly--called "antiknock quality"
List the four stokes in the cycle of a gasoline engine.
1. Intake stroke
2. Compression stroke
3. Power stroke
4. Exhaust stroke
The oil used in the lubrication system of an engine combats the effects of what force?
Friction
Name the type of internal-combustion engine that best fits each clue.
a. Hot, compressed air ignites the fuel in the cylinder
b. A spark from the spark plug ignites the fuel in the cylinder
a. Diesel engine
b. Gasoline engine
Special type of jet engine designed to function at very high speeds
Ramjet
Propeller that pulls airplane through the air
Prop
Turbojet with a large fan added at the very front of the engine.
Turbofan
Extends nozzle of a turbojet engine, more fuel is burned here, producing more heating and expansion of gases and giving a great deal of extra forward power
Afterburner
The simplest gas turbine engine is called a __________.
Turbojet
Uses a jet engine to power a propeller.
Turboprop
Name the two men who flew the first powered airplane.
Wilbur and Orville Wright
The narrow opening at the tail end of the rocket
Nozzle
Small rocket used for signaling
Flare
Chemical compound rich in oxygen
Oxidant
Cargo that rides in the nose of the rocket
Guided military rocket
Missile
Place in a rocket where fuel is burned
Combustion chamber
For next 7 questions, answer either solid-fuel rocket engine (S) or liquid-fuel rocket engine (L)

Used to propel fireworks into the air
S
Can be turned off and restarted again inflight or on the ground
L
Used in most military rockets and missiles
S
Used in space shuttle booster rockets
S
Used only in large rockets
L
Used in all ancient rockets
S
Allows craft speed and direction to be controlled in flight
L
(T/F) rocket engines do not need oxygen in order to burn their fuel.
False (require oxygen)
(T/F) a gasoline engine could operate in outer space.
False (no oxygen)
The first rockets used gunpowder as the propellant.
True
(T/F) Kerosene is the best fuel for a liquid-fuel rocket.
False (liquid hydrogen)
A special form of potential energy that is stored in fuels
Chemical energy
Steam from the boiler enters a hollow __________ fitted inside with a piston.
Cylinder
Spins the fan blades at the front of an engine.
Turbine