1-3 Flashcards
What is the sum of any number and its opposite?
Zero
What is absolute value?
The distance or number of units from zero
What is the result of addition?
Sum
What is the result of subtraction?
Difference
What is the result of multiplication?
Product
What is the result of division?
Quotient
What is the top number of a fraction called?
Numerator
And tells the portion of the bottom number being discussed
What is the bottom number of a fraction called?
Denominator
And tells how many parts there are to the whole number
How do you simplify a fraction?
Divide both the numerator and the denominator by the same non zero whole number until 1 is the only whole number that will divide into both terms of the fraction evenly
What do you have to have in order to add or subtract fractions?
The denominator has to be the same.
Either multiply or divide both the numerator and denominator by the same whole number to get the same denominator
Always simplify at the end
How do you multiply fractions?
Multiply both numerators and then both denominators
Then simplify
How do you divide fractions?
Multiply by its reciprocal
Cross multiply
Then simplify
What do you have to do with mixed numbers before adding subtraction multiplication or division?
Convert mixed numbers to improper fractions
When do you place the decimal point for multiplication?
After multiplying count the decimal places from both numbers and place it that many spots in the answer
When do you place the decimal point when dividing?
Before dividing. Move the decimal point in the divisor to make it a whole number then move the decimal point the same number of spots in the dividend and place the decimal for the quotient above the decimal point of the dividend
How do you add or subtract decimals?
Line up the decimal points then add or subtract
How do you convert decimals to fractions?
Digits to the right of the decimal point are the numerator and the place value as the denominator
.127 = 127/1000
.2 = 2/10
How do you convert a decimal to a percent?
Move the decimal two places to the right and add % sign
How do you convert a percent to a fraction?
Convert percent to decimal and decimal to fraction
How do you convert a percent to a decimal?
Move the decimal two places to the left and drop the %
What is the simplest form of any matter called?
Element
What are the parts of an atom?
Electron
Proton
Neutron
What makes up the nucleus of an atom?
Protons and neutrons
What are the smaller sub-particles of the proton and neutron called?
Quarks
How many times greater is the mass of a proton than the mass of an electron?
1,836 times greater
What are valence electrons?
The electrons in the outer most orbit or shell of atoms
How many valence electrons does a conductor generally have?
One or two
How is the atomic number of an element derived from?
The number of protons in the nucleus
What is the primary source of electrical power?
The flow of electrons
How many electrons can the valence ring hold?
8 electrons
What happens when a conductor is heated?
The resistance goes up
What causes the flow of electrons?
Potential difference
External forces applied
Friction
Chemical
Heat
Pressure
Light
Magnetism
What is electromotive force?
EMF
voltage-E
A potential difference in electron charges
What is current?
Ampere
I
Intensity of Electrical flow
What is voltage?
E
Electromotive force
Electrical pressure
What is resistance?
R
Ohms
Opposition to the current flow
What is power?
P
Watts
Amount of work being done per unit of time
Power is consumed when voltage is applied to a circuit and current flows through the load
What is coulombs?
A fixed quantity of electrons
The number of electrons is measured by the number of coulombs per second that move past a fixed point
Used to measure amps
1 coulomb per second or 1 amp
How many feet in a mile?
5280 ft
What does the prefix kilo mean?
1000
One thousand
What is ohms law?
I=E/R
E=IxR
R=E/I
What system of measurement does most of the world use?
Metric
Name the device that uses the heating of two different metals to produce an electrical potential?
Thermocouple
What type of gas gives off light when current passes through it?
Neon, argon, mercury vapor
What is the thermoelectricity process?
A transfer of electrons when two dissimilar metals are joined together at a junction and then heated
Increase the temperature causes greater transfer of electrons
What happens when you tie a knot in fiber rope?
The knot will derate the WLL of the rope by as much as 45-55% depending on the knot used
What is the most effective way to join two ropes together?
Splice
85-95% efficiency
How much does a bowline knot reduce rope strength?
25%
How much does a hitch reduce the WLL of rope?
25-35%
How do you identify the lay of a wire rope?
The direction the rope strands are twisted
What are the 4 common lays for wire rope?
Right-hand regular-lay
Left-hand regular-lay
Right-hand lang-lay
Left-hand lang-lay
What’s the difference between regular lay and lang lay?
Regular lay the wires in the strand are twisted opposite to the lay of the strands
Lang lay the wires in the strand are twisted the same direction as the lay of the strands
What makes wire rope more flexible?
The make-up of the core
Fiber core is most flexible
What is the advantage of seal stranded wire rope?
It is the least susceptible to wear
When does wire rope need to be replaced?
A loss of diameter of more than 10%
Signs of crushing
Excessive number of broken wires
When setting up a ladder what is the ratio of height vs distance for proper angle?
1/4 one ft out for every 4 ft up
About 75 degrees
Must have 3ft of ladder past top of structure
When working from a ladder on overhead lines what should a worker do?
Always tie off to ladder and tie ladder off to structure
Use bare steel wrench or other tool to slap structure on first and last contact to prevent electrostatic shock
Why is a worker subject to static shock when transferring from a ladder to the tower?
Electrostatic charge and potential difference between the tower and body
How many tie downs do you need when hauling equipment on a trailer?
At least 4 points of tie down
Plus tie down for movable attachments such as bucket or arm
How far away should personal be from excavation equipment while in operation?
6 ft from trencher
Keep a clear zone around equipment
Stay far enough away that any part of the equipment cannot strike anyone
Where can you find specific information for a piece of equipment?
Operator’s manual
To properly place a piece of equipment on a trailer where should the weight of the machine be centered?
Centered over the trailer axles
What is the term for a potentially hazardous situation?
Warning
What is the term for an imminent hazardous situation?
Danger
Who should conduct a job briefing?
The employee in charge of the work to be done
How should you park a piece of equipment on the road?
Park on the right hand side facing the direction of traffic flow
When a load is suspended, can you get off the equipment?
No
What information must be on the MSDS?
Identity of the chemical
The chemical and common names
Physical and chemical characteristics
Physical hazards
Health hazards
Primary route of entry into the body
Permissible exposure limits
Listing for known carcinogens
Any known handling precautions
Any know control measures
Emergency and first aid procedures
Date msds was prepared and revised
Chemical manufacturer info
What is the purpose of hazard communication standard?
To control chemical exposure on the job
Issued by OSHA
Carcinogenicity is an example of a health hazard related to chemical use
Carcinogens cause cancer
Exposure to hazardous chemicals
What class of hard hat is used by electrical workers?
Class E
How long is the test date good for on rubber gloves?
6 months
Electrical hazard shoes are good for how many volts in dry conditions?
600 volts
