Chapter 1 Flashcards
A factor is what?
A factor is a number by which a quantity is multiplied or divided when it is changed from one value to another (ex. might say the power increased by a factor of 2 if it doubled overtime)
A factor is really a _______, its original value divided over its final value
Ratio
If a quantity increased by n% (a certain percentage) then it means, it’s by a factor of ___________
1 + (n/100)
If a quantity decreases by n% then it means it is multiplied by a factor of ___________
1- (n/100) (ex. AN increase of 5% means 1.05 times the original value & a decrease of 4% means its 0.96 times the original value)
When it says “increase by some factor” have to think of the problem, as _________
A proportion (ex. Say A is proportional to B means that if B increases by some factor then A must increase by some factor as well)
If two things are proportional to each other then their ratio are ______ to each other
Equal
Anytime you see a quantity _______ to something then its proportional to it
Equal
The most basic way to indicate the precision of a quantity is to write it with the correct number of ___________
Significant figures (the more sig figs the more accurate the measurement is)
What are the rules for identifying significant figures?
- Nonzero digits are always significant
- Final or ending zero to the right of the decimal point are significant
- Zeros written to the right of the decimal point for the purpose of spacing the decimal point are not significant
- Zeros written to the left of the decimal point may be significant or they may only be there to space the decimal point
- Zeros written between sig figs are significant
How do you do calculations with sig figs?
- When two or more quantities are added or subtracted the answer is as precise as the least precise number (least sig figs)
- When quantities are multiplied or divided the result have the same number of sig figs as the quantity with the smallest number of sig figs
- In a series of calculations rounding to the current number of sig figs should be done at the end not at each step
When info for a problem is missing to get a precise answer you use an ____________ to solve it
Oder-of-magnitude
______________ means “roughly what power of ten?” where we try to keep the number one sig fig
Order - of - magnitiude
W
What are some Prefix abbreviations?
- peta (P) (1015)
- tera (T) (1012)
- Giga (G) (109)
- Mega (M) (106)
- Kilo (k) (103)
- Deci (d) (10-1)
- Centi © (10-2)
- Milli (m) (10-3)
- Micro (M) (10-6)
- Nano (n) (10-9)
- Pico (p) (10-12)
- Femto (f) (10-15)
What are the length conversions?
- 1in = 2.54cm
- 1cm = 0.3937in
- 1ft = 30.48cm
- 1m = 39.37in = 3.281ft
- 1mi = 5280ft =1.609km
- 1km = 0.6214mi
- 1 ly = 9.461 x 1015m
