L1 Multiple Choice
Why are simple machines useful?
a. They make work fun.
b. They make work harder.
c. They make work easier.
d. They can do all the work by themselves.
c. They make work easier.
What kind of machine is a knife?
a. an inclined plane
b. a lever
c. a pulley
d. a wedge
d. a wedge
A pencil sharpener has a __________________.
wheel-and-axle
the use of a force
work
something that makes work easier
simple machine
What is one special trait about a simple machine?
a. It has few moving parts.
b. It cannot do the work of many people.
c. You have to use many forces to make it work.
d. You often need electricity or a battery to power it.
a. It has few moving parts.
What is the difference between a simple machine and a compound machine?
a. a simple machine is made out of two or more simple machines
b. a simple machine is made out of levers
c. a compound machine is made from two or more simple machines
d. a compound machine uses wheel- and-axles
c. a compound machine is made from two or more simple machines
Levers help you ________.
lift
a wheel and an axle that are connected so that they turn together
wheel-and-axle
a wheel with a rope, cord, or chain around it
pulley
What kind of a machine is a see-saw?
a. a pulley
b. a wheel-and-axle
c. a lever
d. a fulcrum
c. a lever
What two kinds of machines make up a pair of scissors?
a. pulleys and levers
b. levers and wedges
c. pulleys and wedges
d. none of the above
b. levers and wedges
The thread around the screw is an _________________.
inclined plane
a bar that pivots, or turns, on a fixed point
lever
the fixed point on a lever
fulcrum
What is an example of doing work?
a. climbing a mountain
b. tying your shoes
c. pulling a wagon full of rocks
d. jumping into a swimming pool
c. pulling a wagon full of rocks
How are a nail and a screw different?
a. a nail takes more force to put into wood than a screw
b. a screw takes more force to screw into wood than a nail
c. a nail can be screwed into a piece of wood
d. all of the above
a. a nail takes more force to put into wood than a screw
Bicycles are _________ __________.
compound machines
a plane that is slanted, so that one end is higher than the other
inclined plane
two inclined planes placed back to back
wedge
What is an example of a machine that uses a wheel-and-axle?
a. a doorknob
b. a bicycle
c. a pencil sharpener
d. all of the above
d. all of the above
Why is a screwdriver considered a wheel-and-axle?
a. It uses a circular motion to do the work.
b. It is attached to a big wheel.
c. It has two axles.
d. It increases the amount of effort you need to put in to get the work done.
a. It uses a circular motion to do the work.
A wedge is two inclined planes placed back to back. One edge is sharp and pointed. The other is _______ and _______.
wide and flat
an inclined plane wrapped around a shaft or a cylinder
screw
a machine made up of two or more simple machines