C4 Terms Flashcards
Mechanics
The scientific study of forces and motion. It consists of kinematics, dynamics and statics.
Kinematics
The science of describing how things move. It involves the measurements and calculations of position, time, velocity, acceleration, and displacement within a reference frame.
Dynamics
The study of how forces affect an object’s motion. Based on Newton’s 3 laws of motion.
Statics
The description of how stationary objects react to pushes and pulls.
System
Part of the universe under study separated from its surroundings by an actual or imaginary boundary.
Surroundings
Everything outside a system’s boundary.
Frame of reference
The geometric space containing the reference point and coordinate axes from which a person observes or measures position and movement.
Coordinate axis
An imaginary line that contains an origin as a point of reference and is marked off in distance units.
Interval
A span of time during which a phenomenon is observed, calculated by subtracting the initial time from the final time. Always a positive number.
scalar
Any measurable property, represented by an italicized symbol, that can be completely described by a single piece of information. It can be either positive, negative, or zero. Includes volume, temperature, time and mass measures.
Vector
A measurable quantity, represented by a bold symbol (or a 1/2 arrow above the scalar symbol), that requires two pieces of information to fully describe it
distance
A positive scalar quantity representing the linear dimension a moving object covers during a time interval. It also may be the magnitude of displacement.
displacement
A vector quantity that describes the net distance and direction of motion. It is represented graphically by a vector arrow whose tail is at the starting point of motion and whose tip is the ending point.
magnitude
The size of any quantity expressed as a positive number in appropriate units.
speed
A scalar quantity that measures the rate of motion of a system. It may also be the magnitude of velocity.
average speed
The average rate of motion over a time interval that accounts for variations in speed. It is a positive scalar quantity.
Velocity
The vector quantity of the rate of displacement of a system or it can be described as speed in a given direction.
acceleration
The rate of change of the speed or velocity of a system during a time interval. It can either be a vector or scalar quantity.
What is mechanics the study of?
forces and motion
Who tried to explain motion by determining why things move?
Aristotle
The early Greek philosopher Aristotle tried to explain _______ things moved.
why
Galileo proposed that we study _______ things move before we conclude ________ things moved.
how
why
________ proposed that we study how things moved before we conclude why they move.
Galileo
________ is generally given credit as the pioneer in the modern study of mechanics.
Newton
Modern physics has divided the study of mechanics into what three parts?
kinematics
dynamics
statics
Which branch describes how things move?
kinematics
What is the branch of mechanics that describes why things move.
Dynamics
A system of reference points from which the position and motion of an object can be determined is referred to as the _______________________.
Frame of reference
What kind of quantities only have size?
scalars
Name some scalar quantities
temperature, mass, time, volume, density, length, area, speed, energy.
Things that have ______ as well as ________ are called vector quantities.
size
direction
Name some vector quantities.
velocity, force, momentum, position in space, acceleration
The _______ moved in a given ________ is called displacement.
distance
direction
Distance and displacement are identical quantities. (T or F)
F