Physics

What is an atom?

Basic unit of matter

Proton is _____ charge

Positive

Neutron is ______ charge

Neutral

Electron is _____ charge

Negative

What does Newton’s law of universal gravitation describe?

Particles attract each other

Porosity is…

Pores where smaller particles may fit.

What does impenetrability means

Two object cannot be in the same space and time

What is matter?

Anything that can occupy space, has mass, and is perceptible

What are the three states of matter?

1. Solid

2. Liquid

3. Gas

Which two forms of matter are incompressible?

1. Solid

2. Liquid

What does liquid do when in a container?

Take the shape of the container

When atmosphere pressure rises, what happens to boiling points?

Changes

What is the formula of density?

Weight / Volume

At 4°C water maximum density is…

62.4lb/ft^3

At higher altitudes, what happens to the performance of an engine?

Decreases

For gaseous matter, why does density decrease as temperatures increase?

Molecules spread out

What is this?

Hydrometer

What is a hydrometer used for?

Measure specific gravity

What is the formula to measure specific gravity

Density of substance / density of water

What is potential energy?

Energy at rest

How do you calculate potential energy?

Weight x height

What is kinetic energy?

Energy at motion

What is the formula for kinetic energy?

½ x mass x velocity^2

How do convert pounds to mass(g)?

pounds/32.2

How do you calculate work?

Force x distance

Is any work done if the object doesn’t move?

No

What is power?

Rate at which work is done over time

What is the formula to calculate power?

(force x distance)/ time

550ft-lb/sec =

1 HP

33,000 ft-lb/minute =

1 HP

746 Watts =

1 HP

How do you calculate horse power?

Force x distance / 33,000ft-lb/min x time

How do you calculate mechanical advantage

Resistance / effort

What is force?

Action that causes object to move

How do you find force?

Area x pressure

How do you find pressure?

Force / area

How do you find volume?

Area x distance

How do you find distance?

Volume / area

In 1st class lever, where is the fulcrum between?

Effort and resistance

In the 2nd class lever, the resistance is between…

effort and fulcrum

In the 3rd class lever, the effort is between…

Fulcrum and resistance

What is the formula to calculate the effort to lift a weight?

L / I = R / E

(Lever) What is the L

Effort arm length

(Lever) What is the i

resist arm length

(Lever) What is the R

Resist force

(Lever) What is the E

Effort force

What do inclined planes do?

Reduce effort by increasing distance over force application

(Inclined planes) What is the L

Ramp length

(Inclined planes) What is the R

Object weight

(Inclined planes) What is the I

Ramp height

(Inclined planes) What is the E

Required effort

What do pulleys do?

Changes force direction and increases mechanical advantage

How do you calculate mechanical advantage for a pully

Count the number of ropes

What type of gear is this?

Spur gear

What type of gear is this

Bevel gear

What type of gear is this?

Worm gear

What type of gear is this?

Planetary gear

Worm gear produce…

extreme mechanical advantage

What do the planetary gear do in high-power aircraft engines?

Decreases propeller shaft speed

How do you calculate the gear ratio?

number of teeth on driven gear / number of teeth on drive gear

What is tension?

Forces pulling apart

What is compression?

Forces pulling together

What is torsion?

Twisting forces

What is bending?

Combination of tension and compression

What is shear?

Forces slicing across an object

What is Newton’s 1st law called?

Law of inertia

Law of inertia describes…

An object at rest stays at rest and in object in motion stays in motion, unless upon by an unbalanced external force

What does Newton’s 2nd law of motion describe?

Forces on an object causes it to speed up

What is the formula of Newton’s second law?

F = mass x acceleration

What does Newton’s third law describe?

For every action, there is an equal and opposite reaction.

What does 1 BTU =

778ft-lbs of work

What is heat?

A form of energy

What is latent heat?

Energy required for substances to change state without temperature change

What is thermal expansion?

Materials expand due to molecular movement, due to increasing temperatures.

What is specific heat?

Amount of heat required to raise the temperature by 1C

What is water’s specific heat?

1

What is conduction?

Heat transfer through direct contact

What is convection?

Heat transfer by fluid movement

What is forced convection?

The use of fans/blowers to increase heat dissipation

What is radiation?

Heat transfer through electromagnetic waves

What is the formula to convert fahrenheit to Celsius?

(f-32)/1.8

What is the formula to convert celsius to farienheit?

1.8 x c + 32

What is atmospheric pressure?

Weight of air above a given point

What does gauge pressure (psig) measure?

Pressure above atmospheric pressure

How do you calculate absolute pressure (psia)?

gauge pressure + atmospheric pressure

What is differential pressure (psid)?

Difference between 2 pressures

What does Boyle’s law describe?

If temperature is constant, pressure and volume are inversely proportional.

What is Boyle’s law formula?

P1 X V1 = P2 X V2

What does Charles’ law describe?

If pressure is constant, volume and temperature are directly proportional

What is Charles’ law formula?

V1/T1 = V2/T2

What does the general gas law calculate?

It calculates pressure, volume or temperature changes in gas

What is general gas law formula?

(P1 X V1)/T1 = (P2 X V2)/T2

What does Dalton’s law of partial pressures describe?

Total pressure of gas equals sum of pressures of each individual gas

How do you calculate pressure?

Height x density

What allows hydraulic fluid to transmit force efficiently?

High molecular cohesion

Buoyancy

Submerged objects go up equal to the weight of the displaced fluid

What does Pascal’s law describe?

Pressure applied to a confined fluid is transmitted equally in all directions

What does Bernoulli’s principle describe?

Increase of fluid velocity, decreases in pressure

How does an aircraft generate lift?

Fast airflow over the top surface of the aircraft wings decreases static pressure

What reduces sound wave transmission?

Lower air density