Simple Machines Study Guide
Vocabulary:
1. Force: any push or pull
2. Gravity: the attraction or pulling force between
objects and the Earth.
3. Friction: the force that slows down or stops
objects in motion
4. Simple machine: a machine with few or no moving
parts. There are six: lever, screw, wheel and axle, pulley,
inclined plane, and wedge.
5. Compound machine: a machine made of two or more simple
machines. Examples
Include a can
opener, a bulldozer, an elevator, etc.
6. Fulcrum: the point where a lever rocks back and
forth
7. Screw: an inclined plane wrapped around a post; it’s used to
hold things together.
8. Wedge: two inclined planes together; it is wide at one end and
pointed at the other. It is used
to split or cut things apart.
9. Energy: the ability to do work
10. Work: occurs when a force moves an object over a distance;
examples, running,
Kicking a
ball, moving furniture, the wind pushing a sailboat, etc. No work is being done sitting still
watching TV, pushing against something that won’t move, etc.
11. Recycling: making trash into something new instead
of throwing it away: items that can
be recycled include glass bottles, some plastics, aluminum, newspapers, etc.
12. Natural resources: things found in nature that people can
use: trees, water,
Metals,
good soil, stone for building, etc.
1. The amount of force needed to move an
object depends on the object’s mass. Heavier things require more force to
move them than lighter things do.
Dragging or pulling a heavy object takes less force than lifting it.
2. Rough surfaces cause more friction than
smooth ones. Rough surfaces can be
smoothed out by adding water, oil, or soap to the surface.
3. Friction is needed to do most
activities safely. For example,
tires with heavy or deep tread stop more easily on snow and slush than do smooth
tires. We couldn’t even walk
without the aid of friction, or drive, or run.
4. To decrease the amount of force needed
to lift a load with a lever, move the fulcrum closer to the load.
5. The longer the inclined plane is, the
less steep it is. The less steep
it is, the less force is needed to move an object up it. But the less steep it is, the longer
the distance is to be traveled.
6. Be able to tell which simple machines
are in common household items. For
Example, a
doorknob is a wheel and axle. An
ax is a wedge and a lever.
7. There are many sources of energy. Some are renewable and some are
not. Children
need to know that renewable means that they can be produced again and
again. Nonrenewable means that
once they are used up, they are gone forever.
Renewable
energy sources: wind, water,
solar, wood, and geothermal.
Nonrenewable
energy sources: coal, oil,
natural gas, and the elements used for nuclear energy. Oil, coal, and natural gas are also
called fossil fuels.
Wood is a
renewable source, but can become nonrenewable if we burn more trees than we can
grow. Likewise with water.
8. Nonrenewable sources of energy need to
be conserved, or used wisely, or we will run out of them. Ways of conserving energy are turning
out lights when they’re not needed; turning down the thermostat at home;
making fewer trips in the car to save gasoline; walking or riding a bike
instead of riding in a car, etc.
Think of some more.
9. Types of energy: heat, light, chemical, sound, and
motion, electrical, nuclear
10. Many products are made from natural
resources: paper comes from trees,
glass is
Made from
sand, plastic comes from oil, soda cans are made from aluminum, etc.