Length and mass are the main ones.
1m, 1kg, etc.
The time ones aren't too difficult (sec, min, hr) but I don't expect to see many of them that you'd have to manipulate.
Scientific notation is really important (so know your orders of magnitude)
I'd say that you should know all your prefixes by now, the important ones anyway:
micro 10^-6
milli 10^-3
centi 10^-2
deci 10^-1
kilo 10^3
mega 10^6
giga 10^9
Anything else is superfluous.
Know your fundamental quantities (standard units, SI)
length - m
mass - kg
time - s
current - A (amperes)
thermodynamic temp - K (Kelvin)
I don't think you'd need to know such things as:
* amount of a substance - mol (moles)
(this is more to do with Chemistry)
* luminous intensity - cd (candela)
That would be about it...
Use your formula sheet too (it's there, why not use it
)
Other minor things:
velocity - m/s
acceleration - m/s^2
force - Newtons (N)
momentum - kg.m/s
energy or work - Joules (J)
power - W (watts)
electric charge - C (coulomb)
p.d. - V (volts)
frequency - Hz
resistance - ohm
E field intensity - N/C (Newtons per coulomb)
That would be it...
(I may have missed a few minor ones
)
Edit
Originally posted by Dash
didn't you mean divide by 10^6 for MHz ???
Originally posted by PoLaRbEaR
Multiplying by 1.0 x 10^9 is the same as dividing by 1.0 x 10^-9
Now I'm confused with all the reciprocals and inverted (negative powers), etc.
Multiply by positive powers to get 'bigger' units (Hz to MHz)
Divide by negative powers to get 'smaller' units (m to nm)
Or you can still multiply by negative powers, but that only complicates things IMO.
Use what works for you, or how your brain works (your own logic will tell you this... I guess?)
LOL...
Multiply by positive indices to get smaller units
Multiply by negative indices to get larger units
Divide by positive indices to get larger units
Divide by negative indices to get smaller units
I don't even know 100% now... :rofl:
