Physics for Aviation Flashcards
What is meant by matter?
Anything that occupies space and has weight
What are the three basic physical states in which matter can exist?
Solid, liquid, and gas.
What is meant by energy?
The capacity for doing work.
What formula is used to find the amount of work done when an object is moved across a floor?
Work=Force x Distance.
What determines the mechanical advantage of an arrangement of ropes and pulleys?
The number of ropes that support the weight.
What determines the mechanical advantage of a gear train?
The ration between the number of teeth on the drive gear and the number of teeth of the driven gear.
What is meant by the fulcrum of a lever?
The point about which the lever rotates.
What are examples of a first-class lever, a second-class lever, and a third-class lever?
First-class: A screwdriver being used to pry the lid from a can of paint.
Second-class: A wheelbarrow.
Third-class: A hydraulically retracted landing gear.
What is meant by pressure?
Force that acts on a unit of area.
What is the standard sea level atmospheric pressure expresed in inches of mercury and in pounds per square inch?
29.92 inches of mercury and 14.69 pounds per square inch.
What characteristic of the atmosphere determines the speed of sound?
Its temperature.
What is meant by a temperature of absolute zero?
The temperature at which all molecular movement stops.
What is the Celsius equivalent of a temperature of 50°F?
10°C.
What are three methods of heat transfer?
Conduction, convection, and radiation.
What is meant by the absolute humidity of the atmosphere?
The actual amount of water that is in a given volume of air.
What causes ice to change into liquid water?
The absorption of heat energy.
What happens inside a solid material when it absorbs heat energy?
The molecules within the material move faster.
What is the basic unit of heat in the English system?
British Thermal Unit.
How much work will one Btu of heat energy perform?
778 foot-pounds of work.
What is the basic unit of heat in the Metric system?
Calorie.
How much heat energy is an a small calorie?
The amount of heat energy that will raise the temperature of 1 gram of water 1°C.
How much heat energy is in a large calorie?
The amount of heat energy that will raise the temperature of 1 kg of water 1°C.
What is the first law of thermodynamics?
Heat energy can neither be created nor destroyed, it can only be changed in its form.
What is the second law of thermodynamics?
Heat energy can only flow from a body having a high temperature to a body having a lower temperature.
What is an example of heat transfer by conduction?
Removal of heat from an engine cylinder by air flowing over its surface.
What is an example of heat transfer by convection?
The uniform heating of air in a room by a floor heater. The heated air rises and forces the cooler air down so it can be heated by conduction.
What is an example of heat transfer by radiation?
The heating of the Earth’s surface by heat transmitted through space from the sun.
Why do most metals expand when they are heated?
As heat is absorbed, the electrons move faster and expand their orbits in the molecules of the metal.