Module 4: Science, Applied Science, and Technology

Question 0

Define force:

Answer 0

A push or pull exerted on an object in an effort to change that object’s velocity.

Question 1

Define simple machine:

Answer 1

A device that either multiplies or redirects a force.

Question 2

Define mechanical advantage:

Answer 2

The amount by which force or motion is magnified in a simple machine.

Question 3

Define diameter:

Answer 3

The length of a straight line that travels from one side of a circle to another and passes through the center of the circle.

Question 4

Define circumference:

Answer 4

The distance around a circle, equal to 3.1416 times the circle’s diameter.

Question 5

How is applied science different from science?

Answer 5

Applied science differs from science in motive (reason for doing something).

In applied science, the goal is to make something better.

In science, the goal is simply to learn.

Question 6

What gives rise to technology?

Answer 6

Technology can result from:

Accident
Applied science
Science

Question 7

Identify the following as a science experiment or an applied science experiment:

An experiment to determine how to make electronic circuits smaller.

Answer 7

It is an applied science experiment because the goal is to make something better.

Question 8

Identify the following as a science experiment or an applied science experiment:

An experiment to understand what factors affect how electricity runs in an electronic circuit.

Answer 8

It is a science experiment because the goal is to learn something.

Question 9

Identify the following as a science experiment or an applied science experiment:

An experiment to figure out how to reduce electronic noise in an electronic circuit.

Answer 9

It is an applied science experiment, because the goal is to make something better.

Question 10

Identify the following as a science experiment or an applied science experiment:

An experiment to figure out the speed of electrons as they flow through an electronic circuit.

Answer 10

It is a science experiment, because the goal is to learn something.

Question 11

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 a longer life
d. An understanding of what causes urinary tract infections in cats

Answer 11

Items “b” and “c” are technology. They are not machines, but a vaccination for animals is something that makes life better, and a new diet or dogs does the same.

Items “a” and “d” are simply pieces of information. They may be useful, but by themselves, they do not make life any better.

Question 12

List six types of simple machines:

Answer 12

lever
pulley
wheel and axle
inclined plane
wedge
screw

Question 13

Which two simple machines look identical?

Answer 13

The inclined plane in the single wedge

Question 14

What is the mechanical advantage equation for levers?

Answer 14

Mechanical advantage = (distance from fulcrum to effort) divided by (distance from fulcrum to resistance)?

What is the mechanical advantage of a first class lever in which the fulcrum is 10 inches from the resistance in 40 inches from the effort?

Mechanical advantage = 40 “divided by” 10 = 4

The mechanical advantage means that the effort is magnified by four. Remember, in first class levers, the mechanical advantage magnifies the force.

Question 15

A shovel is an example of a lever. To what class does a shovel belong?

Answer 15

This is a third class lever.

In a shovel, the part that does not move is the handle. You hold onto the handle with one hand, and you lift the middle of the shovel with the other. Thus, the effort is in the middle of the shovel. The resistance is in the shovels head. Thus, the fulcrum is that one in, and the effort is between the fulcrum and the resistance.

Question 16

A child’s seesaw is a lever. To what class does it belong?

Answer 16

This is a first class lever.

In a see-saw, the middle does not move. One child is the resistance and the other is the effort. Thus, the fulcrum is between the effort in the resistance.

Question 17

What is the mechanical advantage of a wheel and axle?

Answer 17

Mechanical advantage = (diameter of the wheel) divided by (diameter of the axle)

Question 18

What is the mechanical advantage of a wheel and axle when the wheel has a diameter of 15 inches in the axle has a diameter of 3 inches?

Answer 18

Mechanical advantage = (diameter of the wheel) divided by (diameter of the axle)

Mechanical advantage = 15 “divided by” 3 = 5
5 is the mechanical advantage

** When the wheel is turned, a wheel and axle magnifies effort. Thus, the applied force will be magnified 5 times.

** When the axle is turned, speed is magnified. Thus, the wheel will move at 5 times the speed of the axle.

Question 19

A block and tackle is composed of six pulleys that all work together. What is the mechanical advantage of the block and tackle system?

Answer 19

The mechanical advantage of a block and tackle it simply equal to the number of pulleys that work together. Thus, the mechanical advantage is 6.

Using this example, how many feet of rope would have to be pulled if a person wanted to lift a load of 1 foot?

Answer: 6 feet

The mechanical advantage allows you to use less force when you left, but you “pay” for that by having to pull that much more rope. If the person wants to lift the load 1 foot and the mechanical advantage is 6, the person will need to pull 6 feet of rope.

Question 20

What is the mechanical advantage of an inclined plane with the slope of 6 feet and a height of 2 feet?

Answer 20

The mechanical advantage of an inclined plane is given by:

Mechanical advantage = (length of slope) divided by (height)

Mechanical advantage = 6 “divided by” 2 = 3

What is the mechanical advantage of a wedge with the same dimensions as the incline plane mentioned above?

The mechanical advantage equation for a wedge is the same as it is for the inclined plane. Since both have the same dimensions, the mechanical advantage is the same: 3

Question 21

A screw with a pitch of 0.1 inches is turned with a screwdriver whose diameter is 2 inches. What is the mechanical advantage?

Answer 21

The mechanical advantage equation for a screw depends on the circumference of what is being turned. In this case, it is a screwdriver. Thus, we need to calculate the circumference of the screwdriver.

Circumference = 3.1416 x (diameter)

Circumference = 3.1416 x 2 = 6.2832

Now we can use the mechanical advantage equation for a screw:

Mechanical advantage = (circumference) “divided by” pitch

Mechanical advantage = 6.2832 ÷ 0.1 = 62.832

Question 22

If you are having a hard time turning this group, should you get a longer screwdriver or a fatter one?

Answer 22

You should get a fatter screwdriver.

The mechanical advantage of a screw/screwdriver combination is dependent on the circumference of the screwdriver. Thus, the fatter the screwdriver, the better.