Topic 1, 2, 3, 4
What is an example of static electricity in nature?
Lightning
What is a secondary cell?
An electrochemical cell that can be recharged.
What are the three main parts of an electromagnet?
What speeds up the voltage before it enters the transmission lines?
Step-Up Transformer
A current of 13.6 A passes through an electric heater when it is connected to a 100V wall outlet. What is the power of the heater?
P = 1360 W or 1.36 kW
Our house is wired with which type of wiring, series or parallel?
Explain the difference between a wet cell and a dry cell. Use proper vocabulary, hint, the "e" word.
Wet cell has a liquid electrolyte.
Dry cell has a solid paste electrolyte.
What is the difference between a motor and a generator. Use the word "energy" in your answer.
Motor is electrical energy to mechanical energy.
Generator is mechanical energy to electrical energy.
What is the purpose of an Energuide Label on an oven?
It lets us know how much energy a product uses.
A cellphone uses 980J of energy every 60s. How much power does it consume? (to the nearest tenth)
16.3 Watts
What happens to the current of a series circuit if the resistance increases?
What is an anode and a cathode?
They are electrodes, and are two different metals in an electrochemical cell.
What is the purpose of the armature in a motor or generator?
It spins and carries a current across a magnetic field converting electrical energy to mechanical energy.
You would want a lower number because it would use less energy and cost you less monthly.
If an iPod has useful energy of 600J, but 400J of wasted energy, how efficient is it?
60%
What four factors affect the resistance of a wire?
- cross-section diameter
- length
- material
-temperature
A battery is also known as a ______________ pile and converts __________________energy into _______________energy.
voltaic, chemical, electrical
What is a pro and con of alternating current?
Pro - it can go long distances.
Con - it is inefficient.
What is the formula for calculating efficiency?
Useful energy output divided by total energy input x 100%
If the efficiency is 80%, the energy input for a TV is 180J, and the waste energy is 36 J, how many joules of useful energy?
144 Joules
Explain the piezoelectric effect.
Electricity to Mechanical.
When a crystal is connected to a voltage, it expands or contracts slightly, creating sound waves, or vibrations.
What did Alessandro Volta (1745-1827) discover?
That voltage could be generated by placing different metals (electrodes) in a solution containing a salt or acid (electrolytes).
What part makes an AC motor different than a DC motor?
A split ring commutator.
If the Energuide Label says 544 kWh over the year, and the cost per kWh is $0.10, calculate the total cost.
$54.40
If the voltage across a device is 100V and the power that the object uses is 1200W, what is the current that is running through the circuit?
12 Amps