2010 On Line Technocracy Study Course project

Page 22     GO Bottom

In the previous lesson we dealt with the nature and structure of matter, and showed that all matter was composed of some combination of the 92 chemical elements...

Lesson 2


(Part One)

...It was also shown that matter can be changed from one physical state to another, or from one chemical combination to another, but that in any of these processes which occur naturally on the earth matter is not destroyed.

Page 23

      Under what circumstances does matter move? Before this can be answered a number of important relationships involving movements of matter must be investigated.

Units of Measurements.

Measurements of length and distance:
English System:
      12 inches equals 1 foot; 3 feet equals one yard.

Metric System:
      100 centimeters equals 1 meter.

Relation between English and Metric Units:
      2.54 centimeters equals 1 inch.

      The metric system is used universally outside of English speaking countries, and is in general use in all scientific work.

      Mass is that property of matter which is most commonly manifested as weight. Weight, however, is due to the attraction of the earth upon a massive body. Imagine two footballs suspended in space with no gravitational attraction. Suppose one of them was filled with air and the other with lead. Neither would weigh anything, but if a person were given the privilege of kicking one of them he would choose the one with air, otherwise if he kicked the one with the lead he would break his foot. Thus that property of matter that causes it to tend to resist a change of motion is said to be its mass.

Units of Mass.
English System:
      16 avoirdupois ounces equals I pound; 2,000 pounds equals 1 short ton.

Metric System:
      1,000 grams equals 1 kilogram.

Relation between English and Metric units:
      1 pound equals 453.59 grams.

      The unit of time is the second. One second equals one 86400th part of a mean solar day; 60 seconds equals one minute; 60 minutes equals one hour; 24 hours equals one mean solar day.

      Any body at rest or in motion will continue at rest or in the same state of motion unless acted upon by an outside force. Therefore, force is anything that tends to change the state of motion of a mass whether at rest or already in motion. Examples: Pull of stretched coil spring or rubber band, tension on a taut rope, push on the piston of a steam engine, gravitational attraction of earth on a mass, attraction of magnet on iron.

Measurement of Force.
English System:
      A force of one pound is the force the earth's gravitational attraction exerts on a mass of one pound.

Metric System:
      The metric unit of force is the dyne. If a force of one dyne is applied to a freely moving mass of one gram the velocity of this gram mass will be changed by an amount of one

Page 24     GO Top Lesson 2 Bottom

centimeter per second for each second the force is applied. If a force of one dyne is applied to a gram mass originally at rest it will begin to move and continually increase in velocity. At the end of the first second it will have a velocity of one centimeter per second; at the end of the next second its velocity will be two centimeters per second, etc. If the one gram mass is already moving, and a force of one dyne be applied so as to retard its motion, at the end of each second its velocity will be one centimeter per second slower than at the end of the second preceding.

      The pull of gravity on a one gram mass is, at the latitude of New York, 981 dynes. A nickel coin has a mass of about five grams. Thus one dyne is approximately one 5000th part of the pull of gravity on a nickel.

Relation between Dynes and Pounds of Force:
      454 grams mass equals I pound mass. The pull of gravity on 1 gram mass equals 981 dynes. The pull of gravity on 454 grams of mass equals 454 x 981, equals 445,374. Therefore, I pound of force equals approximately 445,500 dynes.

      When a force acts on a body in such a manner as to cause it to move, this force is said to do work on the body. The amount of work done is dependent upon both the magnitude of the force and the distance the body is made to move. Thus the work done is the product of the force applied in the direction of motion and the distance moved.

Measurement of Work.
English System:
      When a force of one pound moves a body a distance of one foot in the direction of the force the work done is one foot-pound. This is true whether the direction is horizontal or vertical.

Metric System:
      When a force of one dyne moves a body a distance of one centimeter the work done is one erg. It requires approximately 5000 ergs to lift a 5c coin a height of one centimeter. Since a dyne is only about one 500,000th part of a pound of force, and a centimeter about one 30th part of a foot it follows that one erg is about one 15,000,000th of a foot-pound. (Exactly, one erg equals one 13,560,000th of a foot-pound.) For practical purposes a larger unit than the erg is required, hence the joule is used. One joule is equal to 10,000,000 ergs; one joule equals 0.738 foot-pounds; one foot-pound equals 1.356 joules.

      Power is the amount of work that is done in a unit of time.

Measurement of Power.
English System:
      If work is done at a rate of 550 foot-pounds per second, or 33,000 foot-pounds per minute, this constitutes a rate of one horse-power (h.p.).

Page 25

Metric System:
      A rate of doing work of one joule per second is a watt. One thousand watts is one kilowatt (kw.). One kilowatt equals 738 foot-pounds per second. One kilowatt equals 1.341 horse-power. One horse-power equals 0.746 kilowatts. A kilowatt-hour (kw.-hr.) is the amount of work done' by a kilowatt of power in one hour; thus a kilowatt-hour is a unit of work instead of power, and is equal to 1,000 joules per second for one hour. Thus one kilowatt-hour (kw.-hr.) equals 3,600,000 joules; thus one kilowatt-hour (kw.-hr.) equals about 2,655,000 foot pounds. The kilowatt hour as given above is exactly the kilowatt-hour for which one pays his monthly electric light bill. One kilowatt-hour will lift a one ton weight a height of a quarter of a mile, or a height greater than the Empire State Building in New York (1248 feet).

GO Top Lesson 2

Go home page



Links to lessons

1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22