Electricity

Question 1

How high DC voltage has to get up to to represent a serious shock risk?

Answer 1

600 volts

Question 2

How high AC voltage has to get up to to represent a serious risk?

Answer 2

As little as 60 volts

Question 3

What should you do if you splash battery acid?

Answer 3

Flush it immediately with freshwater
Neutralize the spill with baking soda
Note: seawater combined with battery acid gives off deadly chlorine gas

Question 4

“What do charging batteries produce?

Answer 4

Both hydrogen and oxygen—a volatile cocktail
Effective ventilation is a battery compartment essential.
Never work on the electrical system while the battery is charging.

Question 5

Why should you never store or mount electronic equipment inside or even near the battery compartment?

Answer 5

Because charging batteries give off corrosive fumes which are especially harmful to electronics.

Question 6

What causes a conductor to get hot?

Answer 6

Wire too small for the job
Poor connection
Corrosion
All of the above can result in excessive and dangerous resistance

Question 7

What does the fuse protect?

Answer 7

The wire (not the appliances the wire supplies)

Question 8

What is an Amp?

Answer 8

A measurement of electrical current

Question 9

What does an Amp measure?

Answer 9

The flow of electricity in a wire by counting the number of electrons per second that pass a sensor.

Question 10

What is a volt?

Answer 10

A measurement of potential

Higher voltage forces a greater flow of electron

Question 11

What is an Ohm?

Answer 11

A measurement of resistance

The flow of electrons is similarly conducted or resisted based on the size and composition of conductors

Question 12

What is a watt?

Answer 12

A measurement of power

Rate at which work gets done

Question 13

What is Ohm’s law?

Answer 13

I (amp) = V (volt) / R (ohm)

Current is directly proportional to voltage and inversely proportional to resistance.

Question 14

What is power?

Answer 14

P (watt) = V (volt) * I (amp)
Rate of doing work
The higher the wattage of a lightbulb, the more light

Question 15

How much current does an appliance draw?

Answer 15

I (amp) = P (watt) / V (volt)

Question 16

What is polarity?

Answer 16

By convention we think of an electrical current as flowing from positive to negative
But the flow of electrons is actually from the negative or ground terminal to the battery’s positive terminal

Question 17

What is series?

Answer 17

Components are connected end-to-end like railroad cars
The total voltage is the sum of the individual voltages
The total resistance is the sum of the individual loads

Question 18

What is parallel?

Answer 18

Components are connected in such a way that there is an alternative path for the current to follow.
Source voltages don’t aggregate in parallel, it creates a “bigger” 12-volt battery, one with a capacity equal to the sum of the individual battery ratings.
The total resistance is a combination of their individual resistances, but not a direct sum.