Physics 6103 - Vocabulary Flashcards: General College Physics for Health Sciences

Vocabulary flashcards covering key terms and definitions from the lecture notes.

Measurement

The process of comparing an unknown quantity with a known quantity or with a standard.

International System of Units (SI)

A system of base units for measurements (meter, kilogram, second, Kelvin, ampere, mole, candela).

SI base units

Seven fundamental units: length (meter, m), mass (kg), time (s), temperature (K), electric current (A), amount of substance (mol), luminous intensity (cd).

Derived quantities

Quantities expressed as combinations of base quantities (e.g., volume, speed, density).

Fundamental quantities

Basic quantities that are independent of each other (e.g., Length, Mass, Time).

Volume

A derived quantity representing the space occupied, formed from base quantities (length^3).

Unit conversions

Changing from one unit to another (e.g., 1 m = 3.28 ft; 1 km = 1000 m).

Metric prefixes

Prefixes used to denote powers of ten (e.g., kilo-, milli-, micro-).

Significant figures

Digits in a measurement that contribute to its accuracy; rules govern which zeros are significant.

All non-zero digits are significant

Rule: any digit that is not zero is significant.

Zeros between non-zero digits are significant

Rule: zeros between non-zero digits count as significant.

Zeros at the end of a number with no decimal point are not necessarily significant

Rule: trailing zeros without a decimal may not be significant (context-dependent).

Accuracy

Closeness of a measured value to the accepted or true value.

Error

Difference between a measured value and the true value; sources include human, systematic, and random errors.

Precision

Reliability of a result; how close repeated measurements are to each other.

Velocity

Distance travelled per unit time (note: as per the notes, velocity is a vector defined as the rate at which an object changes its velocity).

Acceleration

Rate of change of velocity; a = (vf − vi)/(tf − ti).

Rectilinear motion

Motion of a body along a straight line.

Uniform motion

Rectilinear motion with constant velocity (no acceleration).

Accelerated motion

Rectilinear motion with changing velocity (nonzero acceleration).

Uniformly accelerated motion

Rectilinear motion with constant acceleration.

vf = vi + a t

Final velocity equals initial velocity plus acceleration times time.

S = v_i t + (a t^2)/2

Displacement under constant acceleration.

vf^2 = vi^2 + 2 a S

Final velocity squared equals initial velocity squared plus two times acceleration times displacement.

Free fall

Motion under gravity; acceleration due to gravity acts on the body.

g (gravity)

Acceleration due to gravity (approximately 9.8 m/s^2 downward).

Law of Inertia

A body at rest stays at rest and a body in motion stays in motion unless acted on by a net external force.

Mass

A measure of a body's inertia; resistance to changes in motion.

Weight

Gravitational force acting on a mass (weight = m g).

F = m a

Newton's second law: net force equals mass times acceleration.

Newton (N)

Unit of force in the MKS system; 1 N causes 1 kg to accelerate at 1 m/s^2.

Dyne

Unit of force in the CGS system; 1 dyne accelerates 1 g by 1 cm/s^2.

Action–Reaction (Newton's Third Law)

For every action force, there is an equal and opposite reaction force.

Friction

Force that resists relative motion between two contacting surfaces.

Static friction

Friction when an object is at rest; harder to start motion than to keep it moving.

Kinetic friction

Friction when surfaces are sliding; generally less than static friction.

Coefficient of friction

Ratio of frictional force to the normal force between surfaces.

Normal force

Perpendicular contact force exerted by a surface on an object.

Vector

A quantity with both magnitude and direction, represented by an arrow; head indicates direction.

Scalar

A quantity with magnitude only (no direction).

Vector addition

Combining vectors to obtain a resultant; methods include parallelogram and polygon (head-to-tail).

Parallelogram method

Tail-to-tail vector addition; form a parallelogram and the resultant is the diagonal.

Polygon (head-to-tail) method

Sequential addition of vectors; resultant is from origin to final head.

Equilibrant

A vector equal in magnitude to the resultant but opposite in direction.

Resultant

The vector sum of two or more vectors.

Components of a vector

The x- and y-components obtained using cosine and sine of the angle.

Displacement

A vector representing the change in position.