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General
PHYSICS
Question | Answer |
---|---|
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 pressure? | Force that acts on a unit of area. |
What is the standard sea level atmospheric pressure expressed in inches of mercury, and in pounds per square inches? | 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 the density of air? | The weight of a given volume of air. |
How much force is produced by 1,000 psi of hydraulic pressure acting on a piston whose area is 20 square inches? | 20,000 pounds. |
What is meant by the fulcrum of a lever? | The point about which the lever rotates. |
Give an example 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 |
How many cubic inches of fluid is forced out of a cylinder by a piston whose area is 20 square inches when the piston moves five inches? | 100 cubic inches. |
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 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 ratio between the number of teeth on the drive gear and the number of teeth on the driven gear. |
What will happen to the pressure of a confined gas if the temperature of the gas is increased? | The pressure will increase. |
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. |