Question | Answer |
What's earth's revoilution | 30km/s |
_____ is always used in science | metric |
measures work | joule |
a unit is eather ____, _____, or ______ | meter liter gram |
change | convert |
the distance the object travels in one unit of time | speed |
what is the formula for speed | speed = ___distance___ time |
means a steady pace | constant speed |
speed and direction of an object | velocity |
___ _____ ________ must keep very close tracksof the velocity of air craft | air traffic controler |
have the most stressful job | air traffic controler |
the hard outer layer of the earth | lithosphere |
dividing line | boundary |
a push or pull | force |
the overall force on an object after all the forces are added together | net force |
equal forces acting on one object in oppisite directions | balanced forces |
every object resist any change to its motion, the resistance is called _____ | inertia |
the (SI) unit of mass is the ________ | kilogram |
the amount of matter in an object | mass |
the kind of stuff that all objects are made out of | matter |
state newton's first law of motion | an object at rest will remain at rest and an object that is moving at a constant speed will continue moving at a constant speed unless acted upon by an unbalanced force |
one ______ equal the force required to accelerate one kilogram of mass at 1 meter per second per second | newton |
1 kilogram weighs about ____ | 2.2 pounds |
1 kilometer equals ______ | .6 miles |
a force that pulls down | gravity |
forces working in oppostite directions | friction |
a force that causes an obeject to move in a circle | centripetal force |
any object that travels around another in space | satellite |
the mass of a substancecontained in a unit of volume | density |
a substance that can easily change shape | fluid |
the ability to do work on an object | energy |
name 3 types of friction | sliding, rolling, and fluid |
two solid surfaces that slide over each other ; this creates most friction | sliding friction |
friction that occurs when an object rolls over a surface | rolling friction |
creates the least amount of friction | fluid friction |
when the only force acting on a falling object is gravity | freefall |
state newton's third law of motion | if one object exerts a force on another object then the second object exerts a force of equal strength in the opposite direction on the first object |
an object that is thrown | projectile |
state newton's 2nd law of motion | for every action there is an equal and opposite reaction |
moving away from the center , force pushing an object outward away from the center | centrifugal force |
the rate at which work is done | power |
the larger the acre results in ____ downward pressure | less |
air pressure at sea level is about ______ | 10.bn/cm2 |
at higher elevations there is ___ air above you | less |
a break in the earth's crust where slabs of rock slip past each other | fault |
gas trap | bubble |
cave | cavity |
upside down wing | spoiler |
same bone structure but different function | homogenous structure |
pencil lead | graphite |
why does water expand when frozen | cause it forms a crystal |
______ is less dense than air | helium |
_____ is less dense than water | ice |
______ have to travel faster than earth for orbit | satellites |
the titanic departed from_____ in _______ | england 1912 |
takes place of | displace |
put under water | submerge |
weight = _______ | gravity |
front of the boat | bow |
back of the boat | stern |
change | convert |
what was wright brother's goal | to fly a plane heavier than air |
where did they test their odd vechile | a deserted beach in kitty hawk north carolina |
is a device with which you and do work in a way that is easier or more efficient | machine |
what is the formula for work | F times D |
the force you exert on a machine | input force |
the force exerted by the machine | output force |
is the output force a machine gives you to make work easier | mechanical advantage |
compare the input work to the output work | efficiency of a machine |
a machine who has an efficiency of ____ loses very little work | 95% |
an ideal machine would have efficiency of ___ | 100% |