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Flashcards in Test Review Deck (50)
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1
Q

When like atoms are bonded together chemically, they form…

A

an element

2
Q

What is the smallest division which can be made in a substance and still retain all the properties of the substance?

A

A molecule

3
Q

Water is a _______ because water molecules are composed of two kinds of atoms, hydrogen and oxygen.

A

Compound

4
Q

What is any substance whose molecules are composed of unlike atoms?

A

A compound

5
Q

When two different elements or compounds are mixed together and the molecules do not combine chemically, the substance is known as a …

A

Mixture

6
Q

The state of matter is determined by what two things?

A

Temperature and pressure

7
Q

As molecules of solids are heated, their activity or molecular speed is …

A

Increased

8
Q

Because there can be no lower temperature than that at which molecular motion ceases, it is called …

A

Absolute zero

9
Q

There are two kinds of energy:

Potential energy is due to…

Kinetic energy is due to…

A

The position of a mass

The motion of a mass

10
Q

What is the rate at which work is done?

A

Power

11
Q

What are the two types of velocity?

A

Variable and constant.

12
Q

What is the force or shock which results when the movement of a confined liquid is suddenly arrested or accelerated?

A

Water hammer

13
Q

What are the six types of simple machines?

A
  • The lever
  • The inclined plane
  • The wedge
  • The screw
  • The wheel and axle
  • The pulley
14
Q

Levers of the third class multiply _______ or _______, rather than force.

A

Speed, distance

15
Q

If the wheel is the driving axle, there is a loss in ______ because the driving belt is traveling seven times faster and farther than the driven belt on the axle.

A

Mechanical advantage of speed

16
Q

On simple machines it is impossible to gain both _______ and _______ at the same time.

A

Force, speed

17
Q

What are the four main functions of a gear system?

A
  • Transmit positive force
  • Change direction
  • Change speed
  • Increase or decrease force
18
Q

With an odd number of gears in a simple gear train, the driver and driven gears rotate …

A

In the same direction

19
Q

Most screw threads are said to have a definite number of…

A

Threads per inch

20
Q

The length of the slope of an inclined plane is know as…

A

The effort distance (ED)

21
Q

Describe a lever.

A

A rigid bar which turns around a fixed point.

22
Q

Describe an inclined plane.

A

A slanting surface or ramp used to assist the worker in raising objects against the force of gravity.

23
Q

Describe a wedge.

A

A tool used to separate or hold.

24
Q

Describe a screw.

A

A combination of the principles governing the inclined planes, the wedge, and the wheel and axle into one unit.

25
Q

Describe the wheel and axle.

A

A simple machine consisting of a large handle or circular part which is rigidly secured to a smaller part.

26
Q

Describe a pulley.

A

A wheel that rigidly fastened to a shaft on which it turns and that transmits motion

27
Q

What are the different classes of levers?

A

First Class levers: Fulcrum or pivot is located between the effort and resistance force.

Second Class Levers: Fulcrum is located on one side of both the effort and resistance forces and the resistance force is in the middle .

Third Class Levers: Fulcrum is located on one side of both the effort and resistance forces and the resistance force is at the end.

28
Q

What are the different classes of a wedge?

A

Class 1 - Separating Wedge: A wedge used to split material.

Class 2 - Holding Wedge: A wedge used for its holding power.

29
Q

What are the different categories of a screw?

A
  1. To transmit motion
  2. To apply a tremendous amount of force.
  3. To hold parts together.
  4. To obtain measurements.
30
Q

What are the different classes of the wheel and axle?

A

Class 1: Transmit force

Class 2: Change in speed

31
Q

Give an example of a first class lever.

A
Pliers
Crowbar
Claw hammer
Pickax
Wrench
Tin snips
32
Q

Give an example of a second class lever.

A

Lower control arm
Wheelbarrow
Pedal control

33
Q

Give an example of a third class lever.

A

Arm lifting a weight
Fishing pole
Shovel

34
Q

Give an example of an inclined plane.

A

Loading dock

35
Q

Give an example of each of the two types of wedges.

A
  1. Separating Wedge:
    • Drill Bit Tip
    • Knife
  2. Holding Wedge:
    • Door Stop
36
Q

Give an example of each of the four categories of a screw.

A
  1. To transmit motion
    - A drive screw to move a carriage on a lathe
  2. To apply a tremendous amount of force
    - Screw jack
  3. To hold parts together
    - Bolt and Nut
  4. To obtain measurements
    - Threaded interns of a caliper
37
Q

Give an example of each of the two classes of the wheel and axle.

A
  1. Transmit force:
    - Axle Shaft
  2. Change in speed:
    - Step Pulley
    - 10 Speed Bicycle
38
Q

Give an example of a pulley.

A

Timing belt system

39
Q

Define energy.

A

Capacity to do work

40
Q

Define velocity.

A

Rate a mass travels in a particular direction.

41
Q

Acts in accordance with the law of free falling bodies.

A

Gravity

42
Q

A force that resists the relative motion or tendency to such motion of two bodies or substances in contact.

A

Friction

43
Q

Loss of head at the entrance of a pipe

A

Turbulence

44
Q

A closed space at which all air has been removed

A

Vacuum

45
Q

What is viscosity?

A

Resistance to flow.

46
Q

What is pressure?

A

Force exerted by a substance on a unit of area.

47
Q

What is power?

A

The rate at which work is done.

48
Q

What is the overcoming of resistance?

A

Work

49
Q

What is the rate at which velocity in a mass increases with time?

A

Acceleration

50
Q

What is flow rate?

A

The quantity of a substance that moves past a point in a given time.