MEASURING & CALCULATING

HMWK--STUDY FOR DAILY QUIZ

 1   a] THE ORDER OF MAGNITUDE IS A Exponent of Ten
b] IN THE SI SYSTEM THE ORDER OF MAGNITUDE IS INDICATED BY the prefix

    10⁶      10³     10²    10¹    10⁰    10^-1    10^-2    10^-3    10^-6 
1,000,000   1000    100    10      1     1/10   1/100  1/1000 1/1,000,000
-----|--------|------|------|------|-------|------|------|------|---------
    MEGA    KILO  HECTO   DECA   UNIT   DECI   CENTI  MILLI   MICRO

 2   DO THE METRIC SYSTEM HANDOUT.                                     

 3   THE INSTRUMENT USED TO MEASURE MASS IS balance; WEIGHT IS spring scale

 4   AN EXAMPLE OF SOMETHING THAT WEIGHS 1 GRAM IS a stamp.

 5   a] DEFINE THE STANDARD UNIT OF LENGTH:  meter = distance light travels in 1/299 792 458 sec  Historically it was the distance between 2 marks on a metal bar held at 0^oC, before that 1/10,000,000 the distance between the equator and the north pole.
b] WHAT IS A “RULER”?  Anything with a fixed start and end point.

 6   [a] DEFINE TIME.  the interval between two events.
[b] WHAT IS A "CLOCK"?  Anything with a regular repeating motion. 
[c] NAME 5 INSTRUMENTS FOR MEASURING TIME.
Earth’s rotation on its axis.
Earth’s orbiting of sun.
Heartbeat
Pendulum (grandfather clock)
Electric motor (wall clock motor spins 60/sec)
Quartz watch (a tiny quartz bar can oscillate 32 kilohertz (KHz) if electricity is applied)

 7   [a] DEFINE TEMPERATURE & CALIBRATE.                               
Temperature:  the measure of the average kinetic energy of atoms of a substance.
Calibrate:  to adjust the numbers on a scale so that they match those of a standard.
[b] HOW DO YOU CALIBRATE A THERMOMETER? 
  i] Put it in ice water & mark the alcohol level 0 ^oC
 ii] Put it in boiling water & mark the alcohol level 100 ^oC
iii] Divide the distance between the marks into 50 even spaces, each worth 2 ^oC
[c] HOW DOES A THERMOMETER WORK?
It comes to equilibrium with an object and then measures some temperature dependent property. 
Liquid in Glass thermometers measure volume
Oven thermometers measure voltage.
Digital thermometers measure current.
Dial thermometers measure length.

 8   a] WHAT ARE SIGNIFICANT DIGITS?                                   
Digits measured on an instrument.
b] STATE & GIVE EXAMPLES OF 4 RULES FOR SIGNIFICANT DIGITS.
  i] Digits other than zero are always significant.
       96     2 significant digits
     61.4     3 significant digits
 ii] One or more final zeros used after the decimal point are significant.   4.7200     5 significant digits
iii] Zeros between two other significant digits are always significant.   5.029      4 significant digits
 iv] Zeros used for spacing the decimal point, placeholders, are not significant.   7000           1 significant digits
                  0.00783     3 significant digits

9    Find the number of significant digits and write the rule numbers used.
a] 2804 m         4 significant digits rule 3
b] 2.84 m         3 significant digits rule 1
c] 0.0029 m       2 significant digits rule 2
d] 0.003 068 m    4 significant digits rule 3 & 4
e] 900 m          1 significant digits rule 4
f] 4.06x10⁵ m     3 significant digits rule 3

10   [a] DEFINE FUNDAMENTAL CONCEPT. [b] GIVE 4 EXAMPLES & METRIC UNITS.
[c] DEFINE DERIVED CONCEPT.     [d] GIVE 4 EXAMPLES OF & METRIC UNITS.

11   a] IN THE FACTOR-LABEL METHOD UNIT LABELS (kg,L,oK) ARE TREATED AS ___
WHAT ARE THE UNITS IN THE FOLLOWING CALCULATIONS?
    5 g                       5 g/cm³                  8 cm³
b]  --- x 8 g =  40 g²   [c]  ------- =  0.5     [d]  ------ =  2 cm⁶
    cm³             cm³        10 g       cm³          4 g/cm³     g 

12   [a] WRITE THE WORD SYMBOL & UNIT EQUATIONS FOR DENSITY. 
Density = Mass/Volume       D = M/V    g/mL = g/mL   or kg/L = kg/L
[b] WRITE 3 DENSITY EQUATIONS:  D = M/V, M = DV, V = M/D

13   SHOW GIVEN/FIND, EQUATION, SUBSTITUTION WITH UNITS, & ANSWER
a] FIND THE GRAMS PER CUBIC CENTIMETER OF A 47.5 g, 25 cm3 BLOCK
b] FIND THE GRAMS OF 0.75 L MERCURY [13 g/mL].
c] FIND THE mL OF 54 g OF ALUMINUM [2.7 g/mL].
d] FIND THE g/cm3 OF A 37.5 g BLOCK, 5 cm LONG, 3 cm HIGH, 2 cm WIDE.
e] FIND THE mL OF 200 g OF TITANIUM [4.51 g/mL].
f] FIND THE g/cc OF A 53.7 g BLOCK THAT IS 7 cm x 5 cm x 3 cm.
g] FIND THE POUNDS OF 0.25 L IRON [7.8 g/mL].  [1 lb = 453.6 g]

14   a] THE EGYPTIAN PYRAMIDS ARE BUILT OF LIME STONE [2.273 g/cm3]. 
EACH BLOCK IS 133 cm LONG, 75 cm HIGH, AND 100 cm WIDE. 
HOW MUCH DOES EACH WEIGH, IN GRAMS & POUNDS?  [1,000 g = 2.205 lb]
b] A BALE OF HAY [0.135 g/cm3], IS 90 cm LONG, 60 cm HIGH, & 60 cm WIDE.  HOW MUCH DOES EACH WEIGH, IN POUNDS?  [1,000 g = 2.205 lb]

ANS: 13a] 1.90 g/cm3     [b] 9,750 g         [c] 20 mL       [d] 1.25 g/cm3
 [e] 44.35 mL       [f] 0.511 g/cm3     [g] 4.30 lb
14a] 4,999 lb       [b] 96.4 lbs