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True or false: Friction is a force that resists movement between two objects.
True
What does a lubricant do?
Reduces friction to make movement easier.
What is the law of universal gravitation?
All objects are attracted to other objects according to their mass and distance.
What do we call the ability of someone or something to do work?
Energy
What is kinetic energy?
Energy in motion.
What is potential energy?
Stored energy
Can energy be created or destroyed?
No
Name two forms of energy we get from fossils.
oil, coal, natural gas
Name two kinds of renewable energy.
hydropower, biofuels, geothermal, wind, solar, hydrogen
What do we call vibrations that travel through a material from a source?
sound
false
Wat does Roy G Biv stand for?
Red, orange, yellow, green, blue, indigo, violet
What are the tow kinds of invisible light at each end of the light spectrum?
Infrared and ultraviolet
What do we call it when things become less and less ordered?
Entropy or second law of thermodynamics
True or False: Radiant heat can travel through space.
True
What three things are needed to start a fire?
Oxygen, fuel and heat.
True or False: Electricity flows into your house through a direct current.
False
What is the earth's core made out of?
Mostly liquid iron.
What is the region around a magnet that produces a magnetic force?
a magnetic field
True or False: A magnet powered by an electric current that can be turned off and on is called an electromagnet.
True
What is an inclined plane that's wrapped around a cone or cylinder?
A screw
What lever has the fulcrum in the center and the load and effort on opposite ends?
A first class lever.
What must a wheel have to work?
an axle
What do we call the device that moves around and around a treadmill?
a drive belt
Which pulley system makes work easier - a single-pulley system or a double-pully system?
A double-pulley system.