Formal Definitions Flashcards
Mechanics
significant digits
those digits that are known with certainty followed by the first digit which is uncertain
acceleration
rate of change in velocity, per unit of time
average acceleration
change in velocity over an interval of time divided by the time travel
average velocity
change in displacement over an interval of time divided by the time travel
displacement
distance traveled in a specified direction
equilibrium
the state of an object with no resultant force in any direction (transitional equilibrium) and no resultant moment at any point (rotational equilibrium)
Newtons first law
an object continues in uniform motion in a straight line or at rest until a resultant external force acts
Newtons second law
Force = mass x acceleration Force = rate of change of momentum
scalar
a quantity that has only magnitude
vector
a quantity that has both magnitude and direction
Newtons third law
if body A exerts a force on body B, then body B exerts an equal but opposite force on body A
absolute zero
The temperature at which molecular motion becomes a minimum (approximately - 273 C)
Internal energy
The sum total of the potential energy and the random kinetic energy of the molecules of the substance making up the system
temperature
the property that determines the direction of heat flow between two bodies in thermal contact
amplitude
maximum displacement of a particle from its equilibrium position for an oscillating particle
average speed
change in distance over an interval of time divided b the time travel
angle of incidence
the angle between the direction of travel of the incident wave and the normal to the boundary
Angle of refraction
the angle between the direction of travel of the refracted wave and the normal to the boundary
critical angle
The angle, measured to the normal, at which a ray incident on a boundary between two media, will undergo total internal reflection in the more dense medium.
Forced oscilations
Oscilattions resulting from the application of an external, usually periodic, force,
frequency
the number of complete oscilattions a system makes in unit time
laws of reflection
The angle at which the waves are reflected from a barrier is equal to the angle at which they are incident on the barrier.
Longitudional waves
A wave where the particles of the medium through which the wave travels vibrate parallel to the direction of energy propogation
Transverse waves
wave in which the particles of the medium through
