Reading 1.7 Flashcards
In 1791, French scientists proposed a standard unit of length, which they called the _____ after Greek ___ which means ____
- meter (m)
- metron
- measure
French scientists is 1791 based the length of the meter on ____ of the distance along an imaginary line running from the ___ to the ____
- 1/10,000,000
- North Pole
- equator
In addition to the meter the French scientists also settled on a _____ for designing lengths that are multiples or fractions of a meter
-decimal-based system
a set of based and derived units used worldwide to express distances and quanities of matter and energy
SI units
The SI unit for energy
joule (J)
- 1 kg *(m/s)^2
SI unit for speed
m/s
kinetic energy equation
KE=1/2mu^2
-when mass (m) is expressed in kilograms and speed (u) is in meters per second, the units of KE are kg ∙ (m/s)2, or joules.
which Si unit is 10^21
zetta (Z)
Which Si Unit is 10^18
exa (E)
Which Si Unit is is 10^15
peta (P)
Which Si Unit is 10^12
tera (T)
Which Si Unit is is 10^9
Giga (G)
Which SI Unit is 10^6
mega (M)
Which Si Unit is 10^3
kilo (k)
Which Si Unit is is 10^2
hecto (h)
Which Si Unit is is 10^1
deka (da)
Which SI unit is deci (d)
10^-1
Which Si Unit is 10^-3
milli (m)
Which Si Unit is 10^-6
micro µ
Which SI unit is 10^-9
nano (n)
Which SI unit is 10^-12
pico (p)
WHich SI unit is 10^-15
femto (f)
Which SI Unit is 10^-18
atto (a)
Which SI Unit is 10^-21
zepto (z)
Si base unit for mass
kg
Si base unit for length
m
Si base unit for temperature
kelvin K
Si base unit for time
second s
Si base unit for electric current
ampere (A)
Si base unit for quantity of a substance
mole mol
100 C =. __ F and ___ K. This is the _____ point of H20
- 212
- 373
- boiling point
0 C= __ F & __ K. This is the ___ point of ice
- 32
- 273
- melting
78 C = __ F & ___ K. This is the ___ point of ____
- 108
- 195
- sublimation point of dry ice (solid CO2)
-273 C=___ F= ____ K
- 459
- 0
- Absolute 0
the lowest temperature possible
0 K
Equation F to C
- F=180/100C+32
- reduced=9/5C+32
COnvert C to K
273.15+ C
___ cm= 1 in
2.54
1 L= ___ decimeter
1 cubic decimeter ( a cube 1/10 meter on a side)
Which statistics associated with the Golden Gate Bridge in San Francisco, CA (Figure 1.20), are exact numbers, and which have some inherent uncertainty?
a The roadway is six lanes wide.
b The bridge is 27.4 m wide.
c The bridge has a mass of 381 million kg.
d The bridge is 2740 m long.
e The “FasTrack” toll for a car traveling south is $7.00 (as of July 1, 2018).
exact: a e
uncertainty: b, c, d
the extent to which repeated measurements of the same variable agree
precision
- make multiple measurements and record, if the results are consistent with one another, the balance is precise
- cite range between highest and lowest values or the # +- #
agreement between an experimentally measured value and the true value
-how close a measurement is to its true value
accuracy
all the certain digits in a measured value plus one estimated digit. The greater the number of sig figs the greater the certainty with which the value is known
significant figures
Zeros after a decimal point and after a nonzero digit, as in 3.00 ✕ 108 are significant or no
yes
Are Zeros at the end of a value that contains no decimal point, as in 96,500 significant?
may or may not be
- we need to use scientific notation to indicate whether those terminal zeros are significant
- if those zeros are not significant and serve only to set the decimal point, the value in scientific notation is 9.65 ✕ 10^4
- so 3 sig figs
According to the rules of golf, a golf ball cannot weigh more than 45.97 g, and it must be at least 4.267 cm in diameter. The volume of a sphere is (4/3)πr3, where r is the radius (half the diameter).
a. What is the max density of a golf ball, expressed in grams per cubic centimeter to the appropriate # of sig figs
1.130 g/cm3
In the summer of 2018, Belgan dentist Karl Sabbe set a record by hiking the Appalachian Trail from its southern terminus at Springer Mountain Gerorgia to its northern terminus on the peak of Mt. Katahdin, Maine in 45 days, 7 hrs, 39 min. His hike was 3523 km (2189 miles) long
a. What was Sabbe’s average speed in kilometers per day and miles per day?
b. Which do you think is the weak link in calculating his average speed: the actual distance hiked or the time that it took
a. 77.74 km/day or 48.30 miles/day
b. the trip took 65,259 min which is known to 5 sig figs; one more than the distance hiked (3523 km) Therefore, distance is the weak link
