Aviation Physics/Physical Science

What all things are made of. It's the foundation for any discussion of physics

Matter

A law which means matter can not be created or destroyed but it is possible to change it's physical state

Law of Conservation

An example of the law of conservation

combustion process of liquid fuel and/or water from solid to liquid to vapor among others

How is mass mathematically stated?

Mass = Weight / Acceleration due to gravity

m=w/g

How is weight mathematically stated?

Weight=mass x gravity

What is the only way to change the mass of an object?

add or take away atoms

What is weight?

pull of gravity acting on the mass of an object

What are the six characteristics of matter?

• Mass and weight

• Attraction

• Porosity

• Impenetrability

• Density

• Specific Gravity

What is mass?

measure of the quantity of matter in an object

What is density?

amount or quantity of mass per unit volume

The density of a gas______ in direct proportion to the _____ exerted on it.

Increases, pressure

What is most commonly used as the standard when comparing the densities gasses?

Air

What is the standard chosen by physicists when comparing the densities of all liquids and solids?

Water

What is energy?

gives the capacity to perform work

What device is used to measure the specific gravity of a liquid?

Hydrometer

What are the two types of energy?

Potential and Kinetic

Energy at rest is said to be what type of energy?

Potential Energy

Formula: U = mgh

What are the 3 classifications of potential energy?

• due to position

• due to distortion of an elastic body

• which produces work through chemical action

What is kinetic energy?

Energy being in motion

What is force?

The intensity of an impetus, or the intensity of an input

What is the unit for force is both English and metric systems?

English-pounds
Metric-newtons

What direction would it take more work to move an object? Horizontally or vertically?

Vertically

What are 3 kinds of friction?

• Static Friction

• Sliding Friction

• Rolling Friction

Is sliding friction always more or less than static friction?

always less

Purpose of stall strips on airplaine wings

ensure the wing root stall first

The concept of power involves work, which was a force being applied over a measured distance, but adds on one more consideration. What is that consideration?

Time

What is the formula for work?

Work=Force x Distance

What is the formula for Power?

Power= Force x Distance divided by time

The units for power depend on how ________ and ______ are measured

Distance and time

How many ft/lbs are in one horse power?

550 ft/lbs

How many watts are in one horse power?

746 watts

What is torque as applied to physics?

Torque is described as a force acting along a distance; creates twisting and tries to make something rotate.

What is the formula for torque?

Torque= Force x Distance

In the formula for torque, what does distance value represent?

distance along which the force is applied

What is the definition of a machine?

any device with which work may be accomplished

What are the six simple machine?

• Lever

• Pulley

• Wheel and axel

• Inclined plane

• Screw

• Gear

What is mechanical advantage?

a comparison of the output force to the input force / output distance to the input distance

What are the three basic parts of any lever?

• Fulcrum

• Force or effort

• Resistance

The combination of force and distance applied to a lever creates what force that tries to cause rotation?

Torque

Where is the fulcrum located in a first class lever?

between the effort and the resistance

What is the location of the fulcrum and the effort applied in a second class lever?

The fulcrum is at one end and the effort is applied at the other

What is the only advantage of the single fixed pulley?

to change the direction of the force, or pull on the rope

In a single moveable pulley, what will the weight being lifted always be in relation to the effort being applied?

One half

What are bevel gears used for?

to change the plane of rotation

What gear system has an extremely high mechanical advantage?

The worm gear

Name 5 types of stresses found in mechanical bodies?

• Tension

• Compression

• Torsion

• Bending

• Shear

A type of stress which the forces that tend to pull an object apart

Tension

What is compression?

a force that tries to crush an object

What is torsion?

applied to a material when twisting; combination of both tension and compression

What is shear?

a force that tries to cut or slice through

What's newton's first law state?

A body at rest tends to remain at rest, and a body in motion will remain in uniform motion unless acted on by an outside force

what's newton's second law?

The acceleration produced in a mass by the addition of a given force is directly proportional to the force, and inversely proportional to the mass

• Force equals mass times acceleration

What's newton's third law?

For every action, there is an equal and opposite reaction

What is speed?

a rate of motion

What is velocity?

the rate of motion in a given direction

What is acceleration?

the increase in the rate of motion over a period of time

A vector quantity must have both _______ and ______

Magnitude and direction

What is centrifugal force?

the force that pulls a spinning object away from its center of rotation

What is centripetal force?

the equal and opposite force required to hold the weight in a circular path

What are the 3 method of heat transfer?

• Conduction

• Convection

• Radiation

What is the boiling point of pure water in degrees centigrade?

100 degrees C

What is Specific heat?

ratio of the amount of heat energy needed to raise the temperature of an specific mass of material; 1 degrees C

What are the four temperature scales?

• Centigrade

• Fahrenheit

• Kelvin

• Rankine

What is absolute zero?

lowest temperature that is theoretically possible; heat would be minimal

What temperature does absolute zero occur at?

-459.67 F or -273.15 C( 0 kelvin)

What is pressure?

amount of force acting on a specific amount of surface area

What is absolute pressure equal to?

gauge pressure + atmospheric pressure

What is another name for an aneroid barometer?

Altimeter

GAS LAW

What is Boyle's Law?

States that the pressure and volume of a gas is inversely proportional to temperature when constant; GAS LAW

What's Charles law?

stating how gas tends to expand when heated.

end of gas laws

What is a fluid?

Any substance that is able to flow if its not in some way confined or restricted

What is the difference between fluid and gas?

when a force is applied to a liquid it tends to be incompressible thus gases are highly compressible

A solid body submerged in a liquid or a gas weighs less than when weighed in free space. What is this called?

Buoyancy

What is Pascal's law?

concept of the pressure set up in a fluid and how it relates to the force acting on the fluid and the surface area through which it acts

What is Bernoulli's principle?

• flow of a nonconducting fluid, and increase in the speed of the fluid occurs with a decrease in pressure

• Low pressure high velocity; High pressure low velocity

What is sound?

series of disturbances in matter that human ears can detect

What are three things necessary for the transmission and reception of sound?

1. Source

2. medium for carrying the sound

3. detector

What are the two basic physical properties which govern the velocity of sound?

Density and elastictiy

What unit is sound intensity measured in?

decibels

What determines the pitch of sound?

By the vibrations or the sounding source

What is the Mach Number?

ratio of the speed of an aircraft to the speed of sound

What happens to the density of the atmosphere with an increase in altitude?

density of air would decrease

Apparent rise in the pitch or frequency of a sound as its source approached the hearer, and the decrease in pitch as the source moves away

DOPPLER EFFECT

transfer of energy when 2 pieces of matter have the same frequency and one starts to vibrate

RESONANCE

The actual amount of the water vapor in a mixture of air and water.

Absolute Humidity

Temperature to which humid air must be cooled at constant pressure to become saturated.

dewpoint

purpose is to create an aerodynamic force that keeps the flight control in a deflected position

Trim Tabs

It installed on the trailing edge of the stabilator

Anti--Servo Tabs

purpose of aircraft wing dihedral

increase lateral stability

Ratio of water vapor actually present in the atmosphere to the amount that would be present in the air were saturated at the prevailing temp. and pressure

Relative Humidity

In mechanical sense, when is work done?

When a resistance is overcome by a force acting through a measurable distance

It is acting like a balance tab, but rather than assisting the normal force that moves the elevator; sole force that makes the elevator move

Servo Tab

What are the types of pressure?

• static

• Impact

• relative

• absolute pressure

Newton's 3rd Law

Law of Interaction for every action there is an equal and opposite reaction

What atmospheric range provides best conditions for jet aircraft flight?

stratosphere

intensity of hotness or coldness of a mass measured in degrees

TEMPERATURE

Speed of sound in the atmosphere

changes with a change in TEMPERATURE