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43 Cards in this Set
 Front
 Back
What is a comparison of two numbers? 
Ratio 

How many steps are there to convert a decimal to a fraction? 
Three 

What rule specifies a ratio of 1:2:4 for cement, sand, and aggregates for concrete mix? 
Rule 42 

What is a number expressed as a fraction of 100? 
Percentage 

What is the standard metric unit for mass? 
Gram 

What is the boiling point of water at sea level? 
100° c 

What is the point where two lines meet to form an angle called? 
Vertex 

What tool are angles measured with? 
Protractor 

What type of triangle has three sides of different angles? 
Scalene 

What is the measurement of a twodimensional size of a surface called? 
Area 

Formula for the area of a rectangle? 
L x W 

Formula for the area of a triangle? 
B x H x .5 

Formula for the volume of a rectangular shape? 
L x W x D 

What is described as the pushing force behind electricity? 
Voltage 

Voltage is calculated by multiplying current and resistance. What is this formula known as? 
Ohms law 

What is the actual movement of electrons through a conductor known as? 
Current 

What is defined as the opposition of current flow? 
Resistance 

What is the unit of measurement for resistance? 
Ohm 

What is the rate at which work is done called? 
Power 

What is current that flows only in one direction referred to as? 
Direct current 

What is a variable resistor used to limit current flow? 
Rheostat 

What are the smallest building blocks of matter called? 
Atoms 

When atoms combine to form molecules, electrons in the outermost shell are either transfer from one atom to another, or shared between atoms in a process known as what? 
Covalent bonding 

What are electrically charged atoms called? 
Ions 

What does not allow electricity to readily flow through them and have a very high resistance? 
Insulators 

How many amperes could stop a human heart under the right circumstances? 
.1amps 

What states that current is directly proportional to the voltage and inversely proportional to the resistance? 
Ohm’s law 

What is the most common source of DC power? 
A battery 

A battery consist of three main components: positive electrodes, negative electrodes, and what else? 
Electrolytes 

What type of batteries are also known as rechargeable batteries, storage batteries, or accumulators? 
Secondary cells 

What is current flow direction referred to as? 
Polarity 

What type of power source does not have a fixed polarity ? 
AC power 

What is the most commons means of producing either singlephase or polyphase power? 
AC generators 

What principle do generators use to produce voltage and current? 
Electromagnetic induction 

To produce a voltage you need to have a conductor, magnetic field, and what else? 
Relative motion 

What has the ability to store a charge and oppose changes in voltage? 
Capacitor 

What is defined as the total opposition to the follow of AC in a circuit? 
Impedance 

What is the power used to do work plus the power stored during part of a cycle by inductance and capacitance and then returned to the power source called? 
Apparent power 

In an AC circuit what is the power actually used to do work? 
True power 

What type of circuit is defined as having more than one current path connected to a common voltage source? 
Parallel circuit 

What type of electrical circuit is defined as a circuit that contains more than one path of current flow and at least two resistors in a series in one of the paths? 
Series parallel 

What are used in a parallel circuit where three or more conductors meet each other? 
Junction 

What provides the physical connection between the power source, overcurrent protection, switch, and the load and provides a return path back through the components so that current can flow back to its place of origin? 
Conductors 