Electricity Flashcards Preview

Science > Electricity > Flashcards

Flashcards in Electricity Deck (22)
Loading flashcards...
1
Q

What are the factors affecting resistance?

A
  • Type of material
  • Cross sectional area: thickness
  • Length: as it increases so does resistance
  • Temperature: increase in temp=increase in resistance
2
Q

What is AC?

A

Alternating current- a flow of electrons that alternates in direction (wall outlet)

3
Q

What is direct current?

A

Direct current- a flow of electrons in one direction (batteries)

4
Q

What are the 9 ways of generating electricity?

A

Wind energy, solar energy, hydropower, natural gas, coal, petroleum, biomass, geothermal, uranium

5
Q

What are 2 advantages and 2 disadvantages about solar energy?

A

Advantages:

  1. Non-polluting
  2. Systems last 15-30 years

Disadvantages:

  1. Expensive
  2. Needs sunny weather
6
Q

What are 2 advantages and 2 disadvantages about wind energy?

A

Advantages:

  1. No emissions
  2. Affordable

Disadvantages:

  1. Requires wind
  2. Possible health risks
7
Q

What are 2 advantages and 2 disadvantages about Hydropower?

A

Advantages:

  1. Reliable
  2. No emissions

Disadvantages:

  1. Environmental impacts (Dam)
  2. Expensive
8
Q

What are 2 advantages and 2 disadvantages about Natural gas, Biomass, Coal and Petroleum energy?

A

Advantages:

  1. Widely available
  2. Abundant supplies

Disadvantages:

  1. Emissions
  2. Transportation is expensive
9
Q

What are 2 advantages and 2 disadvantages about Geothermal energy?

A

Advantages:

  1. Efficient
  2. Low cost

Disadvantages:
1. Expensive to start up

10
Q

What is an advantage and a disadvantage about uranium energy?

A

Advantage:
No emissions

Disadvantage:
Waste

11
Q

What is resistance? Where does it occur?

A

Resistance is anything that impedes, slows or resists the flow of electrons in a circuit. It occurs everywhere in the circuit but the most at the load

12
Q

What is the equation for Power?

A

P= V x I

P= power (w)
V= voltage (v)
I=current (a)

13
Q

What is the equation for current?

A

I= Q / T

I=current(a)
Q= coulombs of charge (c)
T= time (s)

14
Q

What is the equation for consumption?

A

E= P x T

E= energy consumption (kW•h)
P= power rating (w)
T= time (s)
15
Q

What is the equation for resistance?

A

R= V / I

R= resistance (ohms)
P= potential difference (v)
I= current (a)
16
Q

What is the equation for efficiency?

A

EE= EO / EI

EE= efficiency (%)
EO= energy output (j)
EI= energy input (j)

*output is never more than input, efficiency is never more than 100%

17
Q

What is the equation for voltage?

A

V= E / Q

V= potential difference (v)
E= energy (j)
Q= coulombs of charge (c)
18
Q

What is the equation for cost?

A

C= E x R

C= cost ($)
E= energy (j)
R= coulombs of charge (c)
19
Q

What is the ability to do work?

A

Energy [Joules [J]]

20
Q

What is the rate at which electric energy is produced or consumed over time?

A

Electric power

P– Watts or kilowatts

21
Q

What is: “how much electricity you use and are charged for”?

A

Electrical consumption

22
Q

What does electrical consumption depend on?

A
  1. Duration of use

2. Number and efficiency of electrical devices using