Math & Science Period 2 (CND) Flashcards
What is another name used to indicate the hypotenuse of a triangle for calculation purposes?
Travel
What is the length relationship between the run and the offset?
The are equal
What is the length relationship between the run and the travel?
The travel is 1.414 times longer.
What two elements combine to form a water molecule?
Hydrogen and Oxygen
What does the pH scale measure?
Number of hydrogen ions.
What is the pH of neutral water?
7
What is the difference in the hydrogen ion concentration from pH4 to pH5?
10 times as strong.
What effect does acidic water have on ferrous piping materials?
Corrosion
What causes temporary hardness?
Calcium and/or Magnesium bicarbonates.
Why should a hot water tank be set at a temperature below 50*C?
To prevent temporary hardness from settling out.
What is the buoyant force available on a 5ft3 object if it is immersed in water?
Buoyant Force = 312lbs
(Buoyant force = Volume x Density of Liquid)
(Buoyant force = 5ft3 x 62.4lbs/ft3)
What is the volume of an object that weights 925kg when weighted in air, but only 570kg when weighted in water?
.355m3 (925kg-570kg=355kg/1000kg/m3=.355m3)
What will an object with a volume of 0.658ft3 and a weight of 40lb do when placed in water?
Barely float, with most of the object submerged.
Definition of flow rate?
The quantity moving in a pipe.
What is one major contributor to turbulent flow?
High velocity.
What does not affect the pressure loss in the flow of fluids in a piping system?
Static pressure in the piping system.
What is one probable cause of water hammer?
A quick closing valve.
What is the relationship between pressure and velocity in the narrowest portion of a venturi?
Pressure decreases, Velocity increases.
What causes cavitation?
Vapour bubbles forming in a low-pressure area.
What is the relationship between volume and pressure in Boyle’s law?
Pressure increases, Volume decreases.
What are the two variables in Charles’ law?
Direct relationship between temperature and volume.
A single fixed pulley is used to ?
Change the direction of force applied.
A single pulley attached to an object to be lifted?
Will increase your mechanical advantage by a factor of 2.
When multiple pulley arrangements are used to lift objects??
This arrangement will provide significant mechanical advantage.
A lever is a simple machine consisting of a rigid bar and a ?
Fulcrum.
A class three lever will always have a mechanical advantage of?
Less than 1.
A class 2 lever has a mechanical advantage of?
More than 1.
A class 1 lever has its greatest mechanical advantage if the?
Fulcrum is close to the load.
If a lever has a mechanical advantage of 3, this means that?
a 150 pound effort would move a 450 pound resistance.
The mechanical advantage of a lever assembly is a ration of the length of?
The effort arm to the resistance arm.
What type of steel should be used to manufacture wire rope slings?
Improved plow steel .
Why is a wire rope sling considered to be a complex machine with many moving parts?
The wires and strands flex, move and chafe against each other.
How is a Flemish eye for a wire rope sling prevented from coming apart?
A mechanically compressed metal sleeve is placed over the eye splice.
Why is a thimble used in a Flemish eye wire rope sling?
The thimble helps prevent premature wear of the sling’s eye.
what two main parts make up a wire rope clip?
A saddle and a U-bolt.
How is a fist grip clip different from a wire rope clip?
The fist grip clip has two identical components.
How many wire rope clips are applied to a 1” diameter wire rope to make an eye in the rope when the rule of thumb is used to calculate the number of clips needed?
Answer - 4
(The recommendation for the number of clips used to fabricate eyes on wire ropes is to multiple the diameter of the wire rope by 3, round up to the whole number and add 1.)
How is a wire rope clip applied to properly fabricate an eye in wire rope?
The U portion of the wire rope clip must be placed to grip the dead end of the wire rope.
How tight should you turn the nuts to properly attach a clip to wire rope?
Manufacturer’s torque values; after using the sling for about an hour, retorque the nuts.
Are cable laid slings stronger or weaker than comparably sized single-part wire rope slings?
Stronger.
When inspecting wire rope slings before every work shift, what areas of the sling require the most attention?
End fittings, Swaged sleeves and Hardware.
What does the term shock loading mean when applied to rigging equipment?
The sling is exposed to stress by having the load suddenly start or stop.
What are softeners for rigging?
Pads applied to sharp corners of a load.
How are sling leg angles measured?
From the angle of the sling to a line that is horizontal to the load.
What three basic hitch sling configurations are used for almost all hoisting?
Basket hitch, Vertical hitch, and Choker hitch.
Why are synthetic web slings growing in popularity in the hoisting product market?
They are light, strong, flexible, fasten to the load quickly and are very adaptable.
Which rays of sunlight will damage synthetic fibre web slings?
Ultraviolet light rays.
What is the maximum temperature material that can be lifted with a synthetic fibre web sling?
195F or 90C
How is the lifting capacity of a synthetic fibre round sling identified?
By a colour coded, non-loadbearing cover placed over the sling.
What type of material is required for the manufacture of chain slings that are used for overhead hoisting application?
Alloy steel
How are shackles identified as to size?
By the diameter of steel used to make the bow section.
How are shoulder less eyebolts to be used?
For vertical hoist only.
What rigging factor of safety is to be used when personnel are placed in danger by the hoisting procedure?
10:1
What device may a crane require fro extra support when the crane is set up over large underground pipes that can collapse due to machinery weight or vibrations?
A mat placed under the crane to distribute the cranes weight over a larger area.
Why must a crane be set up to be as level as possible?
Lifting capacity of the crane maybe seriously affected if the crane is set up out of level
How should a crane be configured if it is to carry a load from place to place around the job site ?
The boom should be a short as possible and carried as low as possible with the load snubbed to the crane.
What do Alberta Occupational Health and Safety guidelines require the designated crane signaller to wear to make them stand out from other workers on the job site?
Brightly coloured vests or other clothing.
What are the requirements for the quality of scaffolding planking?
Number 1 grade 2” by 10” planks with the structural strength of spruce or better.
How much load are heavy-duty scaffold platforms expected to be able to withstand?
A load ranging from 25 to 75 pounds per square foot of platform.
The creation of electricity is considered to be the?
Altering of one form of energy to another form of energy.
Matter exists in one of several states because of?
The temperature to which the matter is heated.
Amperage is known as the measurement of?
Electrical current flowing through a conductor.
Electrical pressure is measured in ?
Volts
The resistance to current flow of an electrical circuit is expressed in units of resistance called ?
Ohms
Electromagnetism can be produced by?
Protecting underground pipes with electrical currents.
Electrolysis is?
Producing electricity by chemical action.
Cathodic protection for underground piping is provided by?
A metallic rod in the ground connected t the pipe with a conductor.
All circuits will have a power source, a path for electron flow, a control device and a power consumer called a/an?
Load.
The names applied wo various circuits comes from?
The arrangement of conductors and components.
The Ohm’s Law triangle is used to ?
Develop a formula to solve for an unknown quantity in a electrical circuit.
In a series circuit, total resistance is?
The sum of all resistances in the circuit.
In a parallel circuit, total resistance is ?
Less than the smallest resistance in the circuit.
It consists of two coils of wire linked by a common magnetic circuit (iron core).
Basic transformer.
2 reasons for using a transformer?
To step up a voltage,
To step down a voltage.
2 reasons why transformers operate efficiently?
No moving parts,
A magnetic circuit is a complete path of a low reluctance material with no air gap.
The primary winding is connected to the _________ and the secondary winding is connected to the ______.
Input voltage,
Output voltage.
True or False: A transformer can operate using a DC current?
False
How much power is required to operate a 1.2 amp gas valve with 24 volts applied to it?
28.8 VA (Volts x Amps = VA rating)
How is a voltmeter connected to a circuit?
Parallel power On
How is an ammeter connected to a circuit?
Series power On
How is a ohmmeter connected to a circuit?
Parallel power Off.
1 cu ft of water is equal to _____ lbs.
62.4lbs
1 cu ft of water is equal to _____ imp gal.
6.24 imp gal
1 cu ft of water is equal to _____ US gal.
7.5 US gal
1 imp gal of water is equal to ______ lbs.
10 lbs.
1 US gal of water is equal to ______ lb.
8.33 lbs.
1 ft2 is equal to ____ in2
144 in2
1 ft3 is equal to ____ in3
1728 in3
1 m3 of water is equal to ____ kg.
1000kg
1 cu in of water is equal to _____ lb.
0.0361 lb
1” of water column is equal to _____ psi.
0.0361 psi
1 foot head of water is equal to _____ psi..
0.433 psi.
1 cu in of water is equal to _____ oz.
0.0361lb x 16 oz/lb = 0.578oz.
1m of water is equal to ____ kpa.
9.81kpa
1 m3 of water is equal to ___ L
1000L
1L of water is equal to ____ kg.
1kg.
1 boiler HP is equal to ____ BTU.
33,475BTU
Density of air is?
0.076 lb/ft3 or 1.29kg/m3
Hg (Mercury) is?
13.6 times heavier than water.
Relative Density Formula?
Density of Matter = Relative Density x Density of Water or Air.
Co-Efficient of Linear Expansion Formula?
Length of Change = Delta T x Actual Length x Co-efficient of expansion.
Sensible Heat Formula?
BTU = Sensible Heat Value x Delta T x Mass
Latent Heat Formula?
BTU = Latent Heat x Mass
Specific Heat Capacity of Water ?
1 BTU/lbF or 4.20 KJ/KgC
Specific Heat Capacity of Ice or Steam?
0.5 BTU/lbF or 2 KJ/kgC
latent Heat for Fusion/Solidification of Ice-Water?
144 BTUs/LB or 335 KJ/Kg
Latent Heat for Vaporization/Condensation of Water-Steam?
970 BTUs/LB or 2257 KJ/kg
Latent Heat for Vaporization/Condensation of Propane?
154 BTUs/LB or 356 KJ/kg
When using Charles Law, it is necessary to convert both Fahrenheit and Celsius temperatures to ?
To Kelvin for Fahrenheit by adding 460.
To Rankine for Celsius by adding 237.
Formula for Fitting Allowance?
Fitting Allowance(FA) = Throw - Thread Engagement (TE)
What is the volume of an object that weighs 925kg when weighed in air, but only 570kg when weighed in water?
0.355m3
925kg - 570kg = 355kg / 1000kg/m3
How much extra weight would be required to sink a sealed drum with a volume of 2.725m3 and a mass of 22.7kg ? (Add 1kg extra to cause the drum to sink)
=2703.3kg
2.725m3 x 1000kg/m3 = 2725kg - 22.7kg = 2702.3 + 1
What is the pressure exerted by an 80’ head of water?
= 34.64psi
80’ x .433psi
What 2 ways can Pythagorean theorem be written?
a2 + b2 = (Press the square root button - the check mark looking button)c2
Or
a2 - b2 = (Press the square root button - the check mark looking button)c2
