1. created/destroyed
   hot/cold
2. infinite/indestructible
   invisible/intangible

This is a basic tenet of both chemistry and physics. To us, it looks like matter is destroyed every day, but in fact, matter only changes into other forms - sometimes radically.

1. one
   four
2. twenty
   seven

If you said "three," you were almost certainly thinking of solid, liquid and gas. Plasma is the fourth state, rarely found in nature.

1. energy
   neon
2. mass
   water

Matter and energy change back and forth, from one form to the other. So if the opposite of matter is energy, what's antimatter? Umm, it's complicated.

1. heat
   gravity
2. expansion
   friction

The size and speed of the planets in our solar system were likely dictated by a long-ago explosion, in which the sun threw off some of its mass. But it's gravity that keeps the planets in their orbits.

1. directly proportional
   inversely propotional
2. unrelated to
   half of

To be specific, the gravitational attraction between two objects is proportional to both their masses. So in the relationship between the Earth and the sun, the Earth's mass is important as well.

1. three
   four
2. five
   six

Newton is Isaac Newton, of course. He's incorrectly said to have "discovered" gravity, which is a way of saying that he set out simple laws for how everything in the universe moves - acted on by gravity, one of the universes's fundamental forces.

1. first
   second
2. third
   this is not one of Newton's laws

The rest of the law says, "... unless acted on by an outside force." Why, then, does everything seem to stop moving unless repeatedly propelled? Because there's always an "outside force" in normal conditions on Earth: air resistance, gravity or friction are the main ones.

1. constancy
   enthalpy
2. inertia
   inevitability

The word "inertia" comes from the Latin "iners," meaning "lack of skill." "Inertia" has been borrowed by psychologists and life coaches to characterize a state of psychological paralysis or inaction.

1. the equator
   the poles
2. sea level
   noon and midnight

212 degrees Fahrenheit is an even 100 Celsius. But things are only so neat at sea level. On Everest, you'd only have to heat the water to 71 degrees C.

1. three
   four
2. five
   an atom is a single unit

It's confusing: We call the atom the fundamental unit of matter, but it's made up of three smaller particles - protons, neutrons and electrons.

1. element
   ion
2. molecule
   quark

Chemical elements are matter in its simplest state - at least, until you get into quantum physics. (A word of advice: Don't get into quantum physics. If you see quantum physics coming, hide in a closet until it goes away.)

1. diatomics
   electrons
2. molecules
   nucleons

"Molecule" is almost literally the Latin words meaning "little mass." The suffix -culus or -cula means "little" or "cute."

1. - 10
   12
2. 10
   32

Again, this is affected by altitude. But it's the usual standard you'll see on containers of antifreeze and the like.

1. day
   hour
2. second
   nanosecond

Technically, this is the speed of light in a vacuum, which has been measured to an accuracy of up to four parts in 1 billion. (Four parts in a billion? Come on, scientists, pull it together! We can't have that kind of uncertainty!)

1. true
2. false

Considering that some light sources in the universe are moving really fast, it's best not to think about this one too long. Your head might start to hurt.

1. Bernoulli's
   Nye's
2. Hooke's
   Tyson's

Daniel Bernoulli was a Swiss mathematician and scientist. He came from a family of intellectuals, so he was probably just keeping up when he researched and discovered the principle that bears his name.

1. aviation
   computer science
2. nuclear energy
   radiology

Bernoulli's principle explains how an airfoil works. The top is curved while the bottom is not, meaning the air flows faster over the top, exerting less pressure on the top and more on the bottom. At sufficient speed, that pressure differential is all it takes to get a plane in the air.

1. combustion
   drag
2. lift
   thrust

Combustion is key to how an airplane's engine operates, but it's not one of the four forces of flight. These are lift and weight, which oppose each other, and thrust and drag, which do likewise.

1. pitch
   roll
2. shimmy
   yaw

Okay, it's a stretch to call these laws of nature, but we just like aviation physics! Pitch is the plane's "angle of attack," or how its nose is pointed in the air. Roll is the way a plane turns, lifting one wing and lowering the other. Yaw is a subtler side-to-side movement on an imagined flat plane, controlled by a rudder called the vertical stabilizer.

1. carbon
   fire
2. hydrogen
   nitrogen

When you think of life, you might think "oxygen." But carbon is the element that seems to tie all life forms together - aerobic and anaerobic.

1. breathes
   consumes fuel
   responds to stimuli
2. all of these
   just #2 and #3

Biology differs from chemistry and physics in that biology has very few absolute laws. Consistent with this, there's no one accepted definition in biology for "life." However, the basic criteria is that a living organism must have a finite span of existence, grow, consume fuel, create waste, respond to stimuli, and reproduce itself.

1. 21
   28
2. 55
   98

Vani Hari, who blogs as "the Food Babe," lost some credibility a few years back by criticizing airlines for not pumping pure oxygen into the passenger cabins of their planes. She wrote, " ... it's mixed with nitrogen, sometimes at 50 percent." More, we'd hope - Earth's atmosphere is 78 percent nitrogen. (We assume we don't have to tell you the problem with pure oxygen in an airplane cabin.)

1. hydrogen
   oxygen
   sodium
2. all of these
   only #1 and #2

This is, of course, why water is called H20. While many of the earth's bodies of water are saltwater, sodium isn't an integral part of water.

1. electron
   ion
2. proton
   boson

When protons (positively charged) and electrons (negatively charged) are in balance, the atom is neutral. An imbalance creates a positive or negative ion.

1. nuclear radiation
   magnetic radiation
2. a sonic boom
   static electricity

Yup, this truly impressive and dangerous force of nature is basically the same thing that happens when you pull newly-dried clothes out of the dryer. During a storm, the clouds are moving past each other at such a rate that when electrically-charged areas collide, lightning is formed.

1. bright line
   dew point
2. Maillard point
   Mason-Dixon line

Technically, air doesn't "create" water, but allows it to condense. You can often find the dew point for your area in the day's weather report.

1. air resistance or friction
   a constant, marked as "k"
2. the scientist's body heat
   the speed of light

In high school physics, you probably heard your teacher mention this - that for the sake for expedience, an equation or principle doesn't take resistance into account. This is true, for example, of the truism that Earth's gravity creates an acceleration of 9.8 meters per second squared. This is only true in a vacuum - a condition that, on Earth, has to be created in the lab.

1. no one knows
   the motion of the earth's rotation
2. the gravitational pull of the sun
   the gravitational pull of the moon

Don't laugh about "the motion of the Earth." This was one of Galileo's early theories, that the oceans sloshed froward and back like water in a moving bowl.

1. air
   lye
2. muriatic acid
   water

It's simpler than it sounds - the substance in question is water. It dissolves a great number of materials, which is important, because this helps it to absorb and carry other substances, including nutrients that plants and animals need.

1. true
2. false

If this were true, the wind at the equator would be about 26,000 miles an hour. That's stiff for our tastes! Fortunately, the Earth's atmosphere rotates along with the Earth.

1. constant
   curvature
2. the speed of light
   both #1 and #3

Unpacked, this equation says that the energy of a body equals its mass times the speed of light squared. The speed of light is a constant, therefore can be represented by c, which is often "constant" in math or physics.

1. color
   toxicity
2. pressure
   temperature

Imagine squeezing a plastic bottle with a loosely-closed lid. If you think the lid might fly off, you're right, and this is Boyle's Law in action.

1. air itself
   soil
2. paper
   zinc

This rule of nature is famous because of the Ray Bradbury novel "Fahrenheit 451." It's about a world in which books are illegal, and "firemen" are paid by the government to find and burn them.

1. averages
   impenetrability
2. enthalpy
   inertia

Some rules of physics are so simple they make the reader think, "Well, duh." This is one of them, but physicists would tell you it's important to define the basics before moving on to concepts that aren't so obvious to understand.

1. true
2. false

This is a really complicated subject, but Einstein's theory of special relativity allows for it. It just doesn't look anything like it does in Hollywood. The short answer is this: Jumping into a machine and coming out at the Globe Theater in time to see the first showing of "Hamlet" is almost certainly not going to be possible.