Heat Transfer
A metal spoon will feel colder on your skin than a wooden spoon of the same temperature because metal is a good _________.
Conductor of heat.
Like charges ______
Opposite charges _____.
Like charges repel.
Opposite charges attract.
Amperes, or Amps
When grains of pollen or dust are put in hot water, they vibrate seemingly on their own, and this motion is called _______ ________.
Brownian Motion
How many electrons orbit an oxygen atom normally?
8 electrons to match the 8 protons in the nucleus
The huge cooling towers we see outside of power plants and the sweat on our skin both use the evaporation of water to get rid of heat, a form of:
convection
These two kinds of particles make up the nucleus.
Protons and Neutrons
This device generates a voltage by dissolving two different metals in acid, or by some other kinds of chemical reaction.
Battery
Atoms in the same column of the periodic table have the same number of _________ __________.
Valence electrons.
If phosphorous undergoes radioactive decay and releases two protons, what element does it become?
Phosphorous - Atomic Number 15
Aluminum - Atomic Number 13
The greenhouse effect occurs because the atmosphere traps the radiation that is emitted by:
The Earth (NOT the sun!)
Certain conductors, when cooled down enough, can become a _______, which means they can carry electric current without any resistance.
Superconductor
According to Ohm's Law, the current and the resistance in a circuit have a ________ ________ relationship.
Inversely Proportional
Sweating, your body's method for dealing with excess heat, is an example of this kind of heat transfer:
Convection.
I have 300 grams of water at 20 degrees celsius, and I need to raise it to boiling point. How much energy, in joules or calories, will it take? If I have a 200 W immersion heater to do the boiling, how long will it take?
24000 cal or 100560 J
502.8 seconds or approx 8 minutes 23 seconds
Summarize Newton's Law of Cooling:
The rate of heat transfer between two objects depends on how big a difference in temperature there is between them.
Every charge is surrounded by lines of force. These lines tell us what direction the electric force will push other charges that come close. These lines are referred to as the:
Electric Field
The curly, energy efficient lightbulbs we use nowadays make light through this way.
Fluorescence (Compact Fluorescent Bulbs)
Earth's magnetic field protects us from high energy charged particles emitted by the sun, known as the _______ _______.
Solar wind
What is the resistance of a circuit that has a voltage of 120 V and a power of 60 W?
240 ohms
The rapid increase in greenhouse gases in Earth's atmosphere is causing a phenomenon known as:
Global Warming or Climate Change
Any object that has more negative charges on one side and more positive charges on another is said to be:
Electrically Polarized
Series, Parallel
The different power outlets in your home are connected in a ____________ configuration, so that you can unplug a lamp without shutting off your TV, and so on.
Parallel
Please look at the circuit diagram Mr. E is about to put up on the board and find:
a.) Total current in the whole circuit
b.) The power through Resistor 3
Total current is 4 Amps
P3 = 38.4 W