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New Units for Old

Stage: 5 Challenge Level: Challenge Level:2 Challenge Level:2

 

There are seven different Standardised International (SI) units of measurements from which all others are derived. These are:

Name
Phenomenon
Units
meter
Length
m
second
time
s
kilogram
mass
kg
ampere
electric current
A
kelvin
thermodynamic temperature
K
mole
Amount of substance
mol
Luminous intensity
candela
cd

There are 22 derived physical phenomena, shown below. The names, phenomena, units and base units have been mixed up.

  1. Sort them into the correct order and work out how their units may be represented with base SI units.
  2. For each pheonomena, how many examples of biological application can you find? Can you find an example from biology for each one of these processes?
Name
Phenomenon
Units
Base units
becquerel, Bq
capacitance
A / V
$\quad\quad$m$^2$m$^{-2}$cd
degrees Celsius, $^\circ$ C
electric
conductance
C / V
$\quad\quad$K
coulomb, C
electric
potential
cd sr
$\quad\quad$kg s$^{-2}$ A$^{-1}$
farad, F
electric
resistance
J / kg
$\quad\quad$m kg s$^{-2}$
gray, Gy
electrical
charge
J / kg
$\quad\quad$m$^{1}$m$^{-1}$
henry, H
energy
J / S
$\quad\quad$m$^{2}$ m$^{-4}$ cd
Hertz, Hz
flux of light
$\quad\quad\quad$lm / m$^2$ $\quad\quad$m$^{2}$ kg s$^{-2}$
joule, J
force
$\quad\quad\quad$N / m$^{2}$ $\quad\quad$m$^{2}$ kg s$^{-2}$ A$^{-1}$
katal, kat
frequency
N m
$\quad\quad$m$^{2}$ kg s$^{-2}$ A$^{-2}$
lumen, lm
illuminance
V / A
$\quad\quad$m$^{2}$ kg s$^{-3}$
lux, lx
inductance
V s
$\quad\quad$m$^{2}$ kg s$^{-3}$ A$^{-1}$
newton, N
magnetic flux
W / A
$\quad\quad$m$^{2}$ kg s$^{-3}$ A$^{-2}$
ohm, $\Omega$
magnetic
flux density
Wb / A
$\quad\quad$m$^{-2}$ kg$^{-1}$ s$^{3}$ A$^{2}$
pascal, Pa
plane angle
$\quad\quad\quad$Wb / m$^2$ $\quad\quad$m$^{-2}$ kg$^{-1}$ s$^{4}$ A$^{2}$
radian, rad
power
  $\quad\quad$m$^{2}$ s$^{-2}$
siemens, S
pressure
  $\quad\quad$m$^{2}$m$^{-2}$
sievert, Sv
radiation
dose
  $\quad\quad$sA
steradian, sr
solid
angle
  $\quad\quad$s$^{-1}$
tesla, T
temperature
  $\quad\quad$s$^{-1}$ mol
volt, V
unit of catalytic activity
   
watt, W
     
weber, Wb
     

(data sourced from the Bureau International des Poids et Mesures http://www.bipm.org/)

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Try Universal Time, Mass, Length to investigate the units implicit in the fundamental constants of nature.