Sound is produced when objects ....
vibrate
move
travel
fly
Sound can travel through solid objects.
True
False
A rigid bar that pivots or turns around a fulcrum.
A wheel and axle.
A lever.
A pulley
Most of our electricity comes from _______________
energy stations
train stations
playstations
power stations
The strength or energy that moves an object.
Force
machine
A slanted surface that makes it easier to move an object between a lower level and a higher level.
screw
wedge
Inclined plane
level
any device that uses energy to help a person do work.
power
energy
force
machine
any basic devices that work with the use a single force
compound machines
complex machines
simple machines
washing machines
Sound can't travel through water.
False
True
The point/area around which a lever pivots or turns.
lever
screw
gear
fulcrum
Sound doesn't travel all directions.
False
True
Coal, oil and gas are
renewable sources
non-renewable sources
Most mirrors are made of a sheet of ____________ with a thin coat of _____ on the back
polished glass, silver paint
a rough surface, sand paper
polished plastic, gold paint
unpolished glass, silver paint
Energy can be obtained (taken) from ________ or ___________sources.
man-made, natural
hot, cold
renewable, non-renewable
fast, slow
A pin or pole around which a wheel revolves (to go around something).
axle
pulley
lever
wheel
What does 'run-out' mean?
to use something while running outside.
to build something outside
to use all of something and have nothing left.
to run
Which animal uses echoes to find its way in the dark?
A cat
An owl
A bat
A rabbit
Coal, oil and gas are called....
renewable sources
fossil fuels
rocks
solids
How long does it take for coal, oil and gas to form (to be made)?
hundreds of years
millions of years
billions of years
thousands of years
The Sun, wind and water are all __________ energy sources.
non-renewable
renewable
a circular lever, usually a wheel with a rope around it.
Wheel and axle
Inclined plane
Wedge
Pulley
a round object that turns around a pin or pole.
lever
wedge
wheel and axle
screw
When light hits an opaque object a _________ forms on the opposite side of the object.
reflection
shadow
light
We use it to cut objects.
A wedge
A lever
A pulley
Sound can travel when there's no air.
True
False
an inclined plane wrapped around a rod (a metal stick) often used to hold things together.
Screw
level
Wedge
Wheel
Using non-renewable energy sources causes ________-and can harm the environment.
photosynthesis
natural disasters
pollution
wind
the action of moving something,
power
Work
Any devices made up of more than one simple machine.
Complex machine
simple machine
comply machine