COLLEGE PHYSICS

Simple Harmonic Motion

Vibratory motion in which the acceleration is proportional to the displacement and directed toward the equilibrium position.

Period

The time required for one complete oscillation.

Frequency

The number of complete oscillations per unit time.

Amplitude

The maximum displacement from the equilibrium position.

Phase Angle

The angle that expresses the relationship of quantities at different times.

Potential Energy

The scalar product of the average applied force and the displacement; maximum for greatest displacement.

Simple Pendulum

A pendulum with a small heavy bob at the end of a light string.

Center of Percussion

Where the mass of a compound pendulum appears concentrated.

Moment of Torsion

The ratio of torque to the angle of twist produced by that torque.

Simple Angular Harmonic Motion

Motion produced by restoring torque that causes angular acceleration proportional to angular displacement.

Periodic Motion

Motion where a body moves back and forth over a fixed path, repeating motions after a definite time interval.

Compound Pendulum

A pendulum with a mass-bearing support that affects the period.

Resonance

Occurs when a periodic driving force matches the natural frequency of vibration of a system.

Absolute Zero

Theoretical temperature where all molecular motion ceases.

Density

Mass per unit volume of a substance.

Weight-density

Weight per unit volume, commonly used in forces.

Specific Gravity

Ratio of a substance's density to that of a standard substance.

Pressure

Normal force per unit area, present in all points of a liquid.

Mean Free Path

Average distance a molecule travels before colliding with another molecule.

Pascal’s Law

External pressure on a confined fluid increases pressure at every point by that amount.

Boyle’s Law

In a confined gas, if temperature is constant, the product of pressure and volume is constant.

Archimede’s Principle

A submerged body is buoyed up by a force equal to the weight of the fluid displaced.

Surface Tension

A liquid's surface force per unit length.

Rate of Flow

Volume of liquid passing a cross-section per unit time.

Fluid Friction

Measured in terms of the coefficient of viscosity.

Coefficient of Viscosity

Ratio of tangential force per area to the velocity gradient in laminar flow.

Airfoil

Any surface designed to obtain a force from the air in motion.

Thermal Expansion

Property that dictates heat flow direction between objects.

Thermal Equilibrium

Condition with no net heat transfer between two objects.

Thermometer Scale

Relation between a measurable property and temperature.

Thermometric Property

Property that varies predictably with temperature changes.

Expansivity

Fractional change per degree variation in temperature.

Heat

A form of energy associated with the kinetic motion of molecules.

Internal Energy of Ideal Gas

Energy from random or disordered motion of particles.

Thermal Energy

Disordered internal energy within a system.

Calorie

Heat required to change the temperature of 1g of water by 1°C.

British Thermal Unit

Heat needed to change the temperature of 1lb of water by 1°F.

First Law of Thermodynamics

Total energy in a closed system remains constant.

Heat of Fusion

Heat required to change a substance from solid to liquid at melting point.

Heat of Vaporization

Heat required to change a substance from liquid to vapor.

Boiling Point

Temperature where vapor pressure matches the external pressure.

Freezing Point

Temperature lowered by pressure for substances that expand upon freezing.

Triple Point

Condition of pressure and temperature allowing all three phases to coexist in equilibrium.

Critical Point

Condition where liquid and vapor become indistinguishable.

Critical Temperature

Highest temperature for liquefying gas solely by pressure.

Absolute Humidity

Mass of water vapor per unit volume of air.

Specific Humidity

Mass of water vapor per unit mass of air.

Relative Humidity

Ratio of actual vapor pressure to saturated vapor pressure at a given temperature.

Dew Point

Temperature at which air must be cooled for saturation.

Conduction

Heat transfer through direct contact between molecules.