Day 3 January 17, 2013

Agenda  Safety Quiz  Practice News Article (if needed)  English to English Conversions  SI and Metric System  English vs. Metric Practice  Metric to Metric Practice

English to English Conversions

English to English  Convert 86 inches to feet

English to English  Convert.3 feet to miles

English to English  Convert 74 miles to yards

Converting English to Metric

Metric System  This can seem like another language….

Who Doesn’t Use Metric?

USA Myanmar Liberia

Metric System  SI Base Units Meter (m) Kilogram (kg) Second (s) Kelvin (K) Ampere (A) Mole (mol) Candela (cd)

Meter (m)  Base unit for distance  Originally 1/10,000,000 of the distance from equator to the pole  Once defined by the length of a bar of metal  Now- the distance light travels in a vacuum in 3x10 -9 s

Kilogram (kg)  SI base unit for mass  A platinum-iridium bar maintained by the International Bureau of Weights & Measures near Paris, France  By design, approximately the mass of a liter of water

Second (s)  SI base unit for time  Was defined as 1/86,400 mean solar day, but it wasn’t constant  Now defined as 9,192,631,770 vibrations (cycles) of Cesium-133

Kelvin (K)  SI base unit for temperature  Previously called degrees Kelvin ( 0 K)  In 1967 defined triple point (the exact temperature at which water exists as gas, liquid and solid) of water as K  0 0 C equals K

Ampere (A)  SI base unit for electric current  Defined as :The amount of current that will produce a force of.2micronewtons between 2 parallel conductors, (infinitely long and having a negligible cross section) one meter apart in a perfect vacuum.

Mole (mol)  SI base unit for the amount of a substance. The actual number of atoms or molecules in an object.  Official definition is that one mole of any substance contains just as many elementary particles as there are in Carbon-12.

Candela (cd)  SI base unit for the intensity of light  Originally it represented the intensity of an actual candle made from whale tallow at a specified rate in grains/hr.  Replaced with a definition in terms of light produced by an incandescent bulb  Changed again to define the intensity of 1/600000m 2 of a black-body at a temperature of 2042K  Not happy with that - changed to represent the intensity of a single-frequency light at a frequency of 540THz (green) with a power of mW

English to Metric  Convert 14 inches to meters

English to Metric  Practice, Practice, Practice, Practice, Practice, Practice, Practice, Practice, Practice, Practice,

Metric to Metric Conversion

Metric to Metric  Conversions within the Metric System  Start by setting up the relationship between the prefixes: k (unit) d c m µ n

Metric to Metric  Then add the decimal places between the prefixes this will be our template: k (unit) d c m µ n

Metric to Metric  The units that we’ll be using are:  gram (g), liter (L) and meter (m)

Metric to Metric  Once the template is constructed it’s just a matter of moving the decimal point from an original position to the required new prefix.

Metric to Metric  Convert 58cm to km  1. Place the decimal point in the correct position (if not already placed)  58cm = 58.0cm

Metric to Metric  2. From the position in the template we know that the decimal point is going to move to the left. (the position of the prefix c to the prefix k) k (unit) d c m µ n

Metric to Metric  3. Add up the total number of decimal places between the prefix c and the prefix k. Then move the decimal point that number of places. (5) k (unit) d c m µ n

Metric to Metric  4. Install zeros to fill the vacancy between the beginning number and the new number.  58.0cm becomes.00058km

Metric to Metric  The numbers involved NEVER change!  The position of the decimal point and the number of zeros DOES change!

PRACTICE!!!