# Science Review Laws

## Terms

undefined, object
copy deck
What simple machine is a crow bar that pries a door open?
Lever
Name the 6 simple machines
lever, pully, wedge, inclined plane, wheel + axel, screw
2 factors that influence whatever
roughness + pressure
What is something assumed to be stationary so that anything moving can be compared to it?
A frame of reference
What is a force
a push or a pull
What simple machine is an axe blade that chops wood?
Wedge
Give an example of rolling friction
rollerskating
Give an example of sliding friction
Sledding
Give an example of static friction
sitting in a chair
Tug o war=balanced or unbalanced?
unbalanced
in order 2 do work, what 2 things are needed??
1. There must be movement
2.The movement must be in the same direction as the force
What is a machine?
A device which helps make work easter
What is an efficient machine?
A machine which utilizes its input work to get maximum output OR a machine that is as close to 100% efficient as possibel
Velocity is ____ with _____
speed, direction
A mother pushing a stroller=(balanced/unbalanced)
unbalanced
Which machine is really just a modified inclined plane?
Screw
Intertia is...
the tendency if an object to resist change in its motion
Acceleration can/cannot be positive/negative
can/negative
Net force is that..
total amount with the arrows
Ideal is with/without friction/pressure
without friction
If an astronaut runs out of fuel in his jet pack, what can he do to get back to his space station?
Take his jet pack off and push off in the direction of the space station
What is that astronaut going back to its space station an example of? law 1, 2, or 3?
law three
How is a ferris wheel that goes at a constant speed accelerating?
because its always changing direction

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