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About This Quiz
To many of us, "mechanics" are those people who work on cars. But in physics, "mechanics" has a specific meaning. It refers to the study of motion, whether its causes or its action. In other words, mechanics is the branch of physics that explains why texting while driving is a really bad idea. (Not that some people are ever going to get that point). But beyond its everyday applications, basic physics permeates every other field in science. Think that atoms and molecules are only for chemistry class? Think again — how those atoms move is the province of physics. Think that black holes are only studied in astronomy? Not so — there's a whole branch of physics that deals with the energy and motion of the heavenly bodies.Â
What does this mean to you, the person about to take this quiz? It means that as popular as quantum physics has become in recent decades, you don't have to worry about string theory, supersymmetry or the possibility of a multiverse. We're going to keep our feet pretty solidly on the ground. These questions should, instead, take you back to your high school physics class.Â
So, are you ready to revisit what you learned about this most beautiful of sciences? Get ready to test your knowledge now!
"For every action, there is an equal and opposite reaction" is ...
Boyle's Law
Planck's Constant
Newton's Third Law
We feel comfortable saying that this is the only law of physics regularly cited by people with no scientific background whatsoever. Usually, the context is some sort of revenge, like playing a prank on a co-worker who earlier played a practical joke on them. Newton would be SO disappointed.
It's just a proverb, not a law of physics.
Which concept is represented by the letter "g" (again, unless otherwise specified)?
Gain
Goal
Gravity
Gravity is such an important force in physics that the letter "g" is dedicated to it. It shares this honor with "a" for "acceleration," "v" for "velocity," "f" for "force," and several others.
Ground
What is the force that resists or slows motion when two objects are in contact?
Deceleration
Friction
Though we might think of "friction" as something passive, it's actually considered a force of its own. The two objects are exerting this force on each other, and it changes the rate of motion of both.
Tension
Viscosity
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Who formulated the Three Laws of motion?
Bohr
Einstein
Newton
If this answer gave you trouble, so might the rest of the quiz. Which is not to say it's a quiz on famous people in physics, but Isaac Newton and his Three Laws should have come up by your second or third high school physics class. He/they are that fundamental.
Planck
Unless otherwise specified, what does the letter "m" represent in physics?
Motion
Miles
Mass
Don't be fooled--"matter" and "motion" are also important concepts in physics, just not the ones routinely represented by "m." However, you'll rarely see "miles." As in all branches of science, metric measurements are preferred over standard.
Matter
When an object is in motion, what kind of energy does it have?
Boylean
Kinetic
If you're a vocabulary whiz, the name alone probably helped you out here. "Kinein" is the Greek word for "to move," and "kine-" is used in several English words, including "psychokinesis" for the (purported) ability to move objects with one's mind.
Potential
Extraneous
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Which of your physical characteristics is a function of gravity?
Your height
Your weight
OK, we're not physicists; we can't rule out that other aspects of how your body functions are influenced by gravity. But weight is literally a function of gravity—it's how much the earth pulls on you, thanks to your mass. That's why, of course, you'd weight less on the moon or Mars.
Your heart rate
Your hair color
What is a complete absence of matter called?
An empty field
A null sector
A vacuum
Space is a vacuum—you probably knew that—and vacuums can be created on earth, in lab conditions. Otherwise, though, it's pretty hard to find that "air resistance free" space where you could actually run all those pure, unhindered experiments described in basic physics textbooks.
There is not term for this
Okay, but what's the actual definition of "mass"?
Its weight
Its size
The amount of matter in an object
While "mass" seems to refer to an object's size and its weight, what really counts is the amount of matter contained within its dimensions. So a small object with densely-packed molecules—like something made of iron--probably has more mass than a larger rubber ball.
The volume of air an object would hold if hollow
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Which of these forces opposes gravity in a fluid?
Buoyancy
"Buoyancy" is an upward force. We usually think of it in relation to water, where the water exerts pressure on an object like a boat. The upward force is equivalent to the weight of the water that is displaced by the floating object. (Look up "Archimedes' principle" if you want more information on how this works).
Drag
Friction
The weak force
A quantity that has both magnitude and direction is a ...
Rate
Object
Unit
Vector
A vector describes magnitude and direction, and is often represented by an arrow, but—this part might be a little confusing—it's not an object in and of itself, nor does it have position. It helps to think of it as part of the vocabulary of physics, one that you'll understand better and better as you start using it.
What's not factored into most problems on a basic physics exam?
Air resistance
Most physics problems, at the junior high or high-school level, take place in a magic world with no air resistance. Of course, if we had to live in such a world, problems would ensue (even setting aside the obvious, like everyone asphyxiating)--including the impossibility of getting an airplane off the ground!
The weight of an object
The velocity of an object
Gravity
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Mechanics explains a number of phenomena ... but not this one!
Free fall
The flight of birds
Space travel
Time travel
In fact, time travel isn't even a part of physics, overall. Despite the much-ballyhooed concept that time "exists all at once," the only way to leap backward and forward in it would be to NOT be made of matter (which is a part of spacetime). Anybody here not made to atoms? Didn't think so.
An object at rest stays at rest until what happens?
It's acted on by an outside force.
This is the first of the Three Laws of Motion in physics. There is, you might already know, a famous name attached to those laws, but that's a subject for another question. Also, sorry if you checked the "Einstein' answer--we know he overturned a lot of popular beliefs, but not the First Law.
Its molecules grow too hot to allow it to rest.
It is subsumed by a larger object.
According to Einstein, no object is ever really at rest.
True or false: Gravity is a force that exists between all objects.
This is true.
Everything with mass has a certain amount of gravity. The confusion among beginning physics students is that we're so used to discussing gravity only in terms of the Sun, the Earth, and other massive astronomical bodies.
No, they have to be a certain size, or larger.
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The field of mechanics is divided into two sub-fields. They are "kinematics" and what?
Concussives
Dynamics
"Dynamics" is the study of the causes of motion, while "kinematics" studies, or describes, motion itself. If it seems like these two things are so closely related that they shouldn't need to be separate fields, well, there's nothing academia likes more than dividing things up and classifying them.
Informatics
Stasimatics
The pressure of a gas increases as the volume of its container increases. Whose law is this?
Bohr
Boyle
Robert Boyle was an Anglo-Irish physicist and chemist most famous for his law about how gases behave within a closed system. Of course, those last two words are the kicker, a completely closed system being very difficult to find in the natural world.
Einstein
Clerk Maxwell
One of these is NOT one of the "six simple machines." Which one?
Lever
Inclined plane
Pulley
Scale
A machine is something that changes the direction or magnitude of a force, usually amplifying that force. The six simple machines, as defined by early scientists, were the lever, wheel and axle, pulley, screw, inclined plane and wedge.
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The pascal is the standard unit of ______.
Acceleration
Heat
Pressure
If you're a bit confused by this one, it's likely because, informally, we measure pressure in "bars." A "bar" is equal to 100,000 pascals; you'll hear the term frequently in meteorology, where barometric pressure is an important measurement.
The electroweak force
When two objects impact each other, in physics, it's called a/an what?
Collision
While in everyday life we might use "crash," "collision" is the preferred term in physics. The kind of physics you'll study in high school often examines the results—like transfer of energy—that occurs when two objects collide.
Crash
Transfer
Accident
The rate at which an object's position is changing is called its what?
Acceleration
Force
Vector
Velocity
In everyday conversation, we'd often call this "speed." And that term does have a meaning in physics, as well: It's velocity in relation to one fixed point. Why is this important? Because since every object in the universe is in motion, velocity is relative unless defined as "speed" in relation to another body.
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Which word do we use to identify a change in velocity over time?
Acceleration
Pro tip: Don't use the word "deceleration" around physics buffs. There's no such thing! "Acceleration" can be positive or negative, but the same term applies. Think of how "heat" is a concept in physics, but not "cold," because that's only the relative absence of heat.
Force
Revolution
Speed
Force equals mass times what?
Acceleration
This is probably the classic physics equation that people remember long after leaving school. It's so well known that it's been adapted into a "Star Wars"-themed T-shirt: "May the Mass times Acceleration be with you!"
Joules
Pressure
Speed
Which of these represents the pull of gravity on earth?
5 meters per second
8 meters per second
9.8 meters per second
9.8 meters per second, per second
We measure gravity not as a speed, but as an acceleration. Without air resistance, a falling object will accelerate at 9.8 meters per second, per second, until it's stopped by another object (like the ground). Most often, physicists shorten this rate to 9.8 m/s(squared).
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We define ______, at its simplest, as a push or pull on an object.
Exertion
Force
A "force" is something that makes a body move. (Wait, does this include irresistible dance music?) Naturally, the definition gets more complicated outside the realm of science, like in political news, where "outside forces" might be disrupting an unstable regime.
Kinetic energy
Work
What is the term for an object's overall, or final, change in position?
Displacement
We say "final" here because while an object is moving, we might refer to its velocity or acceleration, both having to do with rates of change in position, but when it stops moving, we talk about its displacement—its ultimate change in position.
Rest
Travel
Transfer
You drop a feather and a lead fishing weight off a five-story building. The feather is an inch wide and five inches long; the weight is two inches wide and three inches long. Which one hits the ground first?
The feather
The weight
No need to rack your brain: It's the feather, which is "designed" (so to speak) to trap air and increase resistance. The lead weight has no such properties. If you chose "the same time," you were probably thinking of the brain teaser in which these objects are dropped in a theoretical airless environment, allowing gravity to act on them in the same way and for them to hit the ground at the same time.
They'd hit the ground at the same time,
It's impossible to know without knowing the exact height of the "five-story" building
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Other than his three laws, what is named for Isaac Newton?
The standard unit of pressure
The standard unit of work
The standard unit of force
Force is routinely measured in newtons, whether it's the force of friction, or the forces involved in a collision, and so on. As respected a figure as Newton is in the world of physics, he's unlikely to be the namesake of anything at CERN, where the work being done is based on that of 20th-century quantum physicists.
The cafeteria at CERN
Force times distance equals what?
Exertion
Displacement
Speed
Work
"Work" in physics has a fairly narrow definition: The force must succeed in changing the location of a body. In other words, if you push like mad on a car stuck in mud, but it doesn't move, you have done no work. (Sorry!)
Wait--what's the difference between "pressure" and "force"?
"Pressure" is always atmospheric.
"Pressure" is the ratio of force to area where it's applied.
We know this one's a little confusing. After all, we hear a lot about atmospheric pressure, barometric pressure, and pressure resulting from heat (as in a pressure cooker). However, the word itself simply refers to the way force spreads out over the surface area to which it's applied.
"Force" always results in motion, "pressure" not necessarily.
"Pressure" is always related to heat.
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What is the opposite of vector?
Finite
Insular
Rate
Scalar
The term "scalar" describes something that has magnitude, but not direction. Temperature, for example, is a scalar quantity. Again, this is a term you'll come to understand better as you start using it.
True or false: "Power" is not a term in physics.
True. It's always energy.
False. This is a physics term.
Power is a term related to how energy is used. Essentially, it's work divided by time, and is measured in units called "watts," for the Scottish scientist James Watt. Unfortunately, since it's most often seen on light bulb packaging, some people think that watts only measure light.
What does a "K" usually stand for in physics equations?
Constant
OK, so shouldn't it be "C"? Well, it's likely that this notation came to us from German, where the word is spelled "konstante." Over time, it became standard in physics. (Technically, the individual scientist is welcome to use any letter, but there's a risk of not being understood by others if the work is widely disseminated).
Kilograms
Kinesis
Kilometers
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________ is the ability to do work.
Energy
While in the working world it might be "motivation" or "initiative," in physics, the correct term is "energy." If you've just arrived from biology class, you might think that only living organisms have this capability, but in physics, it's often inanimate objects that do, solely because of the force they can exert, things like balls and rocks have energy.
Power
Potential
Motivation
What is the opposite of kinetic energy?
Static energy
Positional energy
Potential energy
An object at rest, because of its mass and position, has a certain amount of potential energy. Think of a cannonball suspended at a height by a fraying cable. If that cable breaks, the ball has a lot of ability to exert force and do damage.
Scalar energy
You Got:
/35
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