Physics

What is the second number in a standard form called

it is called the base. It must always be 10 in standard form and is always written in exponent form.

What is the first number in a standard form called

it is called the coefficient.

Significant figures

it refers to the number of important single digits (0 through 9) in the coefficient of an expression in scientific notation. The number of significant figures in an expression indicates the confidence or precision with which an engineer or scientist states a quantity.

Laws of indices - fraction raised to a power

the numerator and denominator are raised to the same power. (A/B) m = Am / Bm E.g. (5/6) 2 = 52 / 62 = 25/36 = 0.69

The rules of significant figures

1. All non-zero digits are significant. Example: 1237 =4 sig fig 2. All zeros between non-zero digits are significant. Example: 1207 = 4 sig fig , 120.007 = 6 sig fig 3. All zeros at the left of the number are NOT significant. Example: 0.00032 = 2 sig fig , 0.06 = 1 sig fig 4. When zeros at the right of the number: If there is no decimal, the zeroes are NOT significant. Example: 300 = 1 sig fig Example: 45400 = 3 sig fig b) If there is a decimal, the zeroes ARE significant. Example: 60.0 = 2 sig fig Example: 0.00045300 = 5 sig fig (the 4 zeros at the left of the number do not count, but the 2 zeros at the right of the number do count.

What is the standard form for 0.000621 and 5,720

6.21 x 10^-4 , 5.720 x 10^3

derived quantities and units

All other quantities, are obtained from one or more of the basic/fundamental quantities.

Physical quantity

Any concept that can be measured using a suitable instrument.

The difference between derived and basic quantities

Basic quantities can't be obtained by other quantities while Derived quantities are the combination of basic quantities. E.g Basic quantity- Length/meter, Derived quantity- Volume/meter

Standard form

It is a way of writing down very large or very small numbers easily and without the use of many zeros. It is sometimes called scientific notation. The scientific notation is based on powers of the base number 10.

Basic Quantities names and symbols

Name Symbol Length l Mass m Time t _________________________ Temperature Celsius Kelvin T __________________________ Electric Current ɪ Amount of Matter n Luminous Intensity Lu

Basic Quantities SI units

Name Symbol Meter m Kilogram kg Second s _____________________________________ Degree Celsius °C Kelvin K _____________________________________ Ampere A Mole mol Candela cd

SI units

SI- "systeme international" SI unit- group of internationally agreed units used in science.

derived quantities

The combinations of fundamental quantities to form velocity, acceleration, force, momentum, work, and power.

Basic/Fundamental quantities and units

These are quantities from which all other physical quantities can be derived.