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Units

Units are used to measure and describe quantitative data. A unit of measured is a definite magnitude of a physical quantity defined and adopted by convention or by law that is used as a standard for measurement of the same physical quantity. Any other value of that physical quantity can be expressed as a simple multiple of the unit of measurement.

Utilizing and converting units allows scientists and mathematicians to manipulate data by using ratios. There are two main systems of units. International System of Units, S.I units and Engineering Engineering Units, E.E. Units. S.I. units are the modern form of the metric system. It is comprised of seven bases units. This system is international accepted. Only Burma, Liberia and the United States have not adopted this system of units. E.E. units are another system of units used. This system has inconsistencies in converting and requires different conversion factors.

For example, length is a physical quantity. The metre is a unit of length that represents a definite predetermined length. When we say 10 metres, we actually mean 10 times the definite predetermined length called “metre”.

Dimension EE Units SI Units
Time Second (sec) Second (s)
Length Foot (Ft) Metre (m)
Mass Pound mass (Lbm) Kilogram (Kg)
Force Pound Force (Lbf) Newton (N)

 

Unit Conversions Quantities in Standard Units

1. Write the following quantities in standard units. (a) 0.66 Ms (b) 3.5 km (c) 27 mg (d) 125 cm 2. Compute, in centimeters and meters, the height of a basketball player 6 ft 4 in tall. 3. Is the following statement reasonable? It took 380 L of gasoline to fill up the car's tank. 4. A car trav

Permeability of Wood Species

I can see that a Darcy's law permeability equation exists and is as follows: k = (volume of liquid x length of specimen)/(time of flow x cross-sectional area of specimen x deltaP) In this equation, there are 2 parameters that I do not understand 1) When the equation refers to the "time of flow" (t) what is meant by that?

Conversions

Please convert them (a) 456 cal to joules (b) 22.3 j to Calories (c) 234 kj to Calories (d) 12.4 Cal to joules -Calculate the amount of heat required to heat a 3.5-kg gold bar from 21 degrees celcius to 67 degrees celcius. -If 57 j of heat are added to an aluminum can with a mass of17.1 g, what is its tem

Conversion questions

1. Convert the following numbers to SI: a. 56.8 in = b. 1 year = c. 34.8 atm = d. 8.3 Btu/min = e. 38.96 ft/min f. 98.6 furlongs per fortnight g. 34.5 in pdl h. 15.8 gal/min 2. Perform the following conversions: a. 34.589 Pa to psia b. 34.6 m/s to mph c. 89.6 L to m3 d. 68.4 in3 to ft3 e. 964 slug to lbm f.

Wave patterns

You have an aluminum rod that has a F=400N with a Length of 2m. Aluminum's density (rho) is 2.71 x 10^3 kg/m. It has a diameter of 0.5 mm so use I2r. Find v, velocity.

Calculating mass and thickness

The average density of blood is 1.06 x 103 kg/ m3. If you donate a pint of blood to the Red Cross, what mass of blood have you donated, in grams? (1 pt = 1/2 L, 1 L = 1000 cm3) a. 530 g b. 0.530 g c. 5.30 x 103 g d. 5.30 x 105 g e. 5.30 g The l

Calculating Cost/Gallon

Question: If kerosene costs 130 passi per liter, and one dollar buys 227, what is its cost in dollars per gallon? [1.00 gallon = 3.79 liters] a. $2.17 per gallon b. $6.62 per gallon c. 15 cents per gallon d. 46 cents per gallon

Miles to Meters Conversion

Sixty miles/hour is about how many meters/second? a. 96 b. 112 c. 1.6 d. 27 e. 37 How many significant figures are in 0.0037010? I think their are seven significant figures is that correct?

Angstrom Unit

Given 1 angstrom unit = 10 ^-10 m and 1 fermi = 10 ^--15 m , what is the a. 1 angstrom = 10^5 fermi b. 1 angstrom = 10^-5 fermi c. 1 angstrom = 10^-25 fermi d. 1 angstrom = 10^25 fermi e. 1 angstrom = 10^-15 fermi

Metric Conversions : Speed and Kinetic Energy of the Eurasion Plate

The Eurasian plate, has a mass of 2.5*10^22kg and travels over the Earth's interior at 7 mm yr^-1. Express this speed in m s^-1(note there are 3.15*10^7 seconds in a year). Using the equation for kinetic energy Ek=1/2mv^2 (where m is mass and v is speed) calculate the kinetic energy of the Eurasian plate, give the final answer

SI units

In this equation h has the units J s, c has the units m s^-1, k has the units J K^-1 and T has the units K. Can you determine the units of a? a=hc/5kT

Force

Two snowcats tow a housing unit to a new location at McMurdo Base, Antarctica, as shown in Fig. 4-43. The sum of the forces FA and FB exerted on the unit by the horizontal cables is parallel to the line L, and FA = 4900 N....See Attached

Relating Power to Distance and Speed: Conversion Problems

STEP1: A 240 horsepower car that weighs 4300 lbs beginning at a stop travels 1/10 of a mile. At optimum performance, what is the maximum speed in MILES per HOUR the car can reach? What is the speed in Mi/Hr at 1/15 of a mile? STEP2: In the same car, how many FEET have been traveled (at max performance) when the car reaches th

Temperature Scales

The world seems to think that a new temperature scale is needed, the NurAn degree. On this scale it is decided that water will freeze at 17 degrees NurAn and boil at 167 degrees NurAn. On this scale, what is the body's average core temperature? How about absolute zero? One day a nurse's temperature is measured as 75 degrees NurA

Working with astronomical units.

Astronomical Unit of earth to sun is @ 1.50 x 10^8 km. Speed of light is about 3.0 x 10^8 m/s. Express the speed of light in terms of (AU) per minute.

Conversions

I haven't been in school for 20 years and I have forgotten how to set up a math equation to figure out conversions (US to Metric).

Express physical quantities in different units of measurement.

1) A sphere has a radius 1.500m Find its volume in cm^3. Find its suface area in m^2 and in mm^2? 2) A truncated right circular cone has dimensions: upper base diameter =1.50cm lower base diameter = 4.00cm height = 6.00cm Find its volume in cm^3, m^3, mm^3 3) a person walks 5km in 1,5hr. What is the speed in mi

Converting units.

A hot air balloon contains 28 cu.cm of hot air in it. What is this volume expressed in cu. meters? [We come across several instances in our day to day life where it becomes essential to convert units from one system to another]. Mathematically, the problem is as follows: 28 cm^3 = ____ m^3 ?