a. Simple machine:
device that either multiplies or redirects a force
b. Force:
a push or a pull exerted on an object in an effort to change that objects velocity
c. Mechanical advantage:
the amount by which force or motion is magnified in a simple machine
d. Diameter:
the length of a straight line that travels from one side of a circle to another and passes through the center of the circle
e. Circumference:
the distance around a circle, equal to 3.1416
- How is applied science different from science?
Motive
- What gives rise to technology?
Accident, science, or applied
- Which of the following would be considered technology?
a. A classification scheme for all animals?
b. A vaccination that will keep all animals from contracting the flu
c. A new diet for dogs that will lead to longer life
d. An understanding of what causes urinary-tract infections in cats
B and D are science experiments, because the goal is to learn something. A and C are applied science experiments because the goal is to make something.
- Which two simple machines look identical?
B and C are technology
- List the six types of simple machines
The lever, the pulley, the wheel and axel, the inclined plane, the wedge and the screw.
- What is the mechanical advantage of a first-class lever in which the fulcrum is 10 inches from the resistance and 40 inches from the effort?
The inclined plane and the single wedge
- What does the mechanical advantage in problem #8 mean?
4
- A shovel is an example of a lever. To what class does a shovel belong?
The mechanical advantage means that the effort is magnified by 4
- A child’s see-saw is a lever. To what class does it belong?
Third class lever
- What is the mechanical advantage of a wheel and axle when the wheel has a diameter of 15 inches and the axle has a diameter of 3 inches?
First class lever
- If a person turned the wheel of the wheel and axle in problem #12, what would the mechanical advantage do?
5
- If a person turned the axle in problem #12, what would the mechanical advantage do?
The applied force will be magnified 5 times
- A block and tackle is composed of six pulleys that all work together. What is the mechanical advantage of the block and tackle system?
The wheel will move at 5 times the speed of the axel
- Using the block and tack system in problem #15, how many feet of rope would have to be pulled if a person wanted to life a load 1 foot.
6
- What is the mechanical advantage of an inclined plane with a slope of 6 feet and a height of 1 feet?
6 feet
- What is the mechanical advantage of a wedge with the same dimensions as the inclined plane in problem #17?
3
- A screw with a pitch of 0.1 inches is turned with a screwdriver whose diameter is 2 inches. What is the mechanical advantage?
3
- If you are having a hard time turning a screw, should you get a longer screwdriver or a fatter one?
fatter
