ELE 101 Exam 1

The machine that generates electricity from magnetism is called a

Generator

A five-band color coded resistor has a value equal to 82.5 kohl - what are the colors of the first four bands

Gray red green red

A 56Kohm resistor would have which colors as its first bands

Green blue orange

The _______ contains the general rules and regulations that contractors, builders, and manufacturers, must follow for proper installation and routing of wires

National electric code

A photovoltaic material is one which converts

Light energy into electricity

Direction of electron flow in a circuit is always from

Negative to positive

Electron is a

Negatively charged particle

A 47K ohm resistor would have which colors on its first three bands

Yellow violet orange

Superconductors are materials that exhibit_______ resistance to the flow of electricity

Zero

Thermocouple is used to measure the

Temperature

The areas of a battery that are marked positive and negative are called

Terminals

What best describes the difference between wet cells and dry cells

Wet cells have a liquid electrolyte, while in dry cells the electrolyte is a moist paste

Tools used to remove insulation from wires are

Wire strippers and knives

Convert 540,000,000 to its corresponding scientific notion

5 x 10^7

A tolerance of +-20% on a 1000kohm resistor is

800kohm to 1200kohm

A resistor's first three color bands are white brown red - what is its value

9.1kohm

Convert 95kohm to ohm

95000ohm

Fuses are made from materials, which have a ______ melting point

Low

Soldering is the process of joining metals using another metal that has a _______ melting point

Lower

Materials that allow electricity to flow through them easily are called

Metals

Never touch a capacitor without first

Discharging it

What is the most common electric shock-related injury

Electrical burns

Death caused by electrical shock is called

Electrocution

Which capacitoris polarized

Electrolytic

At its most basic level, a battery is a can full of chemicals that produces

Electrons

Basic parts of a circuit are

Energy source, switch, conductive path and load

A car battery uses zinc paste as its electrolyte

False

A group of batteries make up a cell

False

A primary cell can be recharged

False

A thermocouple consists of two similar metals bonded together

False

Two particles with different charges will repel or drive away from each other

False

Wet conditions decrease the risk of electric shock by lowering skin resistance

False

Unit for capacitance is

Farads

Atomic number is defined as the number of neutrons in an atom

False

Dry cells are normally used in cars and trucks

False

A soldering iron or a soldering gum tip is tinned by coating its surfaces with

Solder

A capacitor

Stores energy or charges

Which wire type is best suited for a lamp cord

Stranded

The three factors that affect capacitance are

Surface area, distance between the plates and the insulating material

What is the device that is used to open and close a circuit

Switch

If two wires have the same cross-sectional area and made from the same material, the long wire will have the lesser resistance

False

Insulators offer very less resistance to the flow of electricity

False

Solid wife is more flexible than stranded wire

False

The fourth stripe in the five band color coded resistors indicates the tolerance

False

Which sized wire is larger #10 or #24

#10

Express 2.01x10^-4 in its normal number notation

0.000201

A resistor's first three color bands are brown, black and black - what is its value

10 ohm

A resistor's first three color bands are red yellow black- what is its value

24 ohm

Constant flow of electrons in one direction in an electrical circuit is called

A dc current

The device that's produces electricity from chemical reaction is called

An electrochemical cell

Liquid in the cell is called

An electrolyte

Safety devices in electrical circuits are

Circuit breakers, fuses and ground fault interrupters

The bigger the gauge (AWG number) of a wire _______ is the size of the wire

Bigger

A thermistor

Changes resistance with changes in temperature

A(n) ______ is used to measure the specific gravity of the acid used in a storage battery

Hydrometer

Devices used to open and close circuits without the inconvenience of disconnecting and reconnecting wires are called

Switches

Atoms that lose or gain electrons become

Ions

What are atoms of the same element having the same number of protons but different number of neutrons called

Isotopes

Atomic mass is defined as the mass of a/an________ of an atom

Nucleus

One way to stop the flow of electrons is to ____ the circuit

Open

Which is an example of a variable resistor

Potentiometers

Piezoelectricity is generated from

Pressure

One of the materials used to produce electricity by pressure is

Quartz

What device inhibits/resists the flow of current in a circuit

Resistors

The best insulators are

Rubber mica and plastic

If replacement capacitors are not available, you should substitute it with a capacitor that has

Same rating, but higher working voltage

Nickel-Cadmium, lithium ion and nickel-metal hydride cells are

Secondary cells

Which of the following statements describes a good solder joint

Shiny, smooth, and concave fillet

Electrical soldering is also called

Soft soldering

Devices used to convert solar energy to electricity are called

Solar cells

When the plate area of a capacitor increases

The capacitance increases

Copper is a good conductor of electricity because

There are many free electrons present in this metal

Sold solder is an alloy of

Tin and lead

A schematic is used instead of a complex, detailed drawing of an electrical circuit

True

Grounding involves providing a conductor to carry current into the ground rather than into a body

True

It is dangerous to charge a non-chargeable battery

True

It's always important to replace a blown out fuse with a proper one

True

Nichrome is used as a heating element

True

Rosin core solder should be used for all electrical soldering

True

True or false: all electrical circuits have to be grounded

True

Tungsten is used to make light bulb filaments

True

Wearing safety glasses is important when soldering

True

Which of three colors is NOT used in the resistor color code

Turquoise

A rheostat is another name for a

Variable resistor