Fluids Terms
Matter
Matter is anything made up of atoms, which are composed of miniscule particles called molecules. Basically, everything in the universe. So molecules are made of atoms which are all matter. The only two properties that matter with matter are mass and volume, no pun intended.States Of Matter
Matter takes on the forms of solids, liquids, and gases. Water is still water whether ywe're putting ice in a drink, boiling it to cook pasta, or drinking some after beating our brother at tennis.Heat Of Vaporization
How much heat is needed to vaporize a quantity of a liquid? That's the heat of vaporization.Scalar
A quantity of something. Could be anything. The number of words in this module is a scalar.Vector
A scalar with direction. We can't read this module by reading any word in any order unless we're masochistic. If we read it as intended, from left to right and top to bottom, then we're following a direction. Think of the direction of an applied force or motion.Force
Forces can be thought of as a push or pull acting in a particular direction. Some usual suspects include the forces of gravity, friction, and magnetism.Newton's First Law
Objects are like us. Once they get comfy, they don't want to move. This is the law of inertia, or the couch potato law as we like to call it. Except for when we think about how hard it is to stop an asteroid: "An object in motion tends to stay in motion" is just as true as "an object at rest tends to stay at rest."Newton's Second Law
In math terms, F = ma. The force applied on an object is equal to its mass times the acceleration it experiences. If the object isn't moving at all, then F = 0. If it's moving but going at a constant speed, then F is also zero. This is known as equilibrium, a kind of boring state where not much happens. Gravity is a force, though, that causes acceleration on falling objects. Look out below!Newton's Third Law
To every action, there's an equal and opposite reaction. Even when gravity hurtles us to the earth, we're pulling back on the earth with our own gravitational force but our mass and gravity are negligible compared to the Earth, so it wins. A bulldozer pushing dirt is opposed by the dirt pushing back on the bulldozer, even when the dirt is moved.Gravity
An attractive force that objects exert on each other based on mass. Think of gravity as superglue for the universe. Without this force, nothing would exist.Weight
Weight is a force, not a mass. In this case, W = mg, where g is the acceleration due to gravity of the Earth. Picture walking on the moon with Neil Armstrong. Weight is a lot less over there, though mass remains the same. This is because acceleration due to gravity on the moon is a lot weaker than on Earth.Normal Force
In vector land, the normal force is the contact force perpendicular from the surface on which an object lies at rest. For surfaces that lay flat horizontally, the normal force points straight up, the opposite direction of the force of gravity. It's what keeps objects from falling through whatever matter lies between it and the center of the earth. For a hill or other inclined surface, the normal force points diagonally up, perpendicular to the surface.Friction
The force opposing a motion. It's air resistance, surfaces rubbing each other and slowing down a motion, or the force creating the great grip of rubber on the road. Friction affects everything. Ice on ice has low friction, and rubber on rubber high friction.Equilibrium
If you ask us, equilibrium should've been spelled EQUALibrium. In equilibrium, every force that acts on an object is canceled out. An object in equilibrium will either stand still or move at constant speed (without acceleration) unless a force changes and puts it out of equilibrium, causing acceleration.Fluid
Fluid is matter that flows under an applied force. Therefore, if we apply a force to something and it flows, it's a fluid. Always remember that matter is made up of millions of particles, so that even if things don't look like they're flowing, they are. And flowing hair might not be a fluid. Just saying.Macroscopic Scale
The real-world scale, as seen by our eyes. And telescopes. But not microscopes.Density
In math terms, we express density as mass divided by volume,
. High density materials such as lead weigh a heck of a lot more than a low density material such as Styrofoam for the same size.Specific Gravity
Nothing to do with gravity, sorry. It's the ratio of the density of a fluid to the density of water. Think of it as specific density (specific to water, that is.)Specific Volume
Physicists are always trying to impress us by coming up with new terms. They could've very well called this one the opposite of density. We like to call specific volume anti-density, since it's simply volume divided by mass, the reciprocal of density.Pressure
Since we're under pressure to understand this module, then we have an idea of what pressure means. Apply force to an object and what happens? We're on the right track if we next ask for what area of the object the force is applied. Pressure is force divided by area,
.