Chapter 1 � Physical Concepts

Chapter 1 � Physical Concepts - Chapter 1 Physical...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 1 – Physical Concepts Standard units of measure are based on physics 1. Numbers, Quantities, Measures, and Dimensions o Scientific notation – simple way to represent large and small numbers with ease; translates any number into the product of a coefficient multiplied by some power of 10 To multiply – add the exponents of the base 10 and multiply the coefficients To divide – subtract the exponents and divide the coefficients Laws of exponents govern computation o Quantification yields a numerical value that reflects size or magnitude o Quantities involving magnitude and direction are vectorial quantities, vectors o Only magnitude – scalars Of like dimensions can be added or subtracted directly o Direction must be taken into account for vectors to fully specify the quantity If directions differ in dimensions, vector analysis methods must be used o Units of measure facilitates universal understanding o Dimensions of physical quantities must be considered when combining them o Dimensions in mechanics and acoustics are length, time, and mass (L, T, M) o Metric system is standard units of measure L – M(eter) M – K(ilogram) T – s(econd) 2. Fundamental Physical Quantities o Time – scalar quantity o Length – distance is a dimension of length and a scalar quantity o Displacement – when an object moves from one place to another, vector, measured in meters o Mass – property of all matter; object can be weightless but never massless; scalar, dimension M measured using a balance in unit of grams (g) o Derived quantities – more complex Area – measure in unit of cm 2 Velocity – combining dimensions of length and time, m/s, vector
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Speed – rate at which distance is transversed, scalar o Velocity – time rate change in displacement, vectorial quantity that much include direction along with magnitude V = difference in x / difference in t Instantaneous velocity when the difference in t = 0 o Acceleration – instant-to-instant changes in velocity a = difference in V / different in t Slowing down – deceleration, denoting negative acceleration Acceleration = 0 when velocity is constant Vectorial quantity with units m/s 2 which signifies time rate change of a time varying quantity o 3 aspects of the motion of an object: Displacement Velocity Acceleration o Force – most fundamental derived quantity, requisite to understanding work, energy, and power Measures of sound magnitude are related to force 3. Force, According to Newton o May be defined as a push or a pull o 3 laws of Isaac Newton; Newton’s Laws: 1 – an object at rest tends to remain at rest; an object in motion tends to maintain its magnitude and direction of its velocity (unless acted upon by an extraneous force) 2 – the net force acting upon an object in motion is equal to the product of its mass and the acceleration imparted to it by the force (in the same direction as the force)
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/18/2011 for the course CSD 1025 taught by Professor Durrant during the Spring '11 term at Pittsburgh.

Page1 / 8

Chapter 1 � Physical Concepts - Chapter 1 Physical...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online