Bias, Number Sense, Order of Magnitude
Human Scale – Meter (10E-6 µm Micrometer to 10+E+3)
- Meter: Human height, House height, Car length
- MicroMeter (10E-6): Microfiber, Microscope, Bacteria
- KiloMeter (10E+6): Distance between home to work, city to city
Back in the year I am doing study of Piezoelectricity, all measurement is based on micrometer (µ), imagine a human hair ranging between 30-100 µm. In the study of Air pollution, the measurement is also based on micrometer, for example PM 2.5 where it less than 2.5 µm or PM 10 which less than 10 µm. A measurement in microscale is simple interesting, as it can be seen using ‘cheap’ microscope in junior high school to study cell to bacteria. But measurement in below micro scale is difficult, for example nanomaterial is difficult to made. Compare with recently popular term of microfibre.
Environment Scale – Mt (Megatonne, 1 billion kg)
- Indonesia energy TPES: 200 MTOE in 2013 ~ perkapita 200 MTOE/200 mill pop = 1,000 kg MTOE per kapita ref
- Indonesia emission: 2.1 GT CO2 in 2005 ~ per kpita 2.1 GT/200 mil pop = 10,000 kg CO2e per kapita
- Forest Fire: 31 Million ha
Environment scale is more abstract, as it on the policy level. The scale that used is megatonne or which is 1 billion kg. It is too big to imagine. Even on why CO2 generated is heavier than original fuel due to chemical reaction with air is concept that difficult to be accepted by the average person (like me), or to understand the emission factor by fuel.
What its mean for me? that the concept of Number Sense is sometimes make bias and inconsistency. Understanding Engineering notation and use it correctly in the order of magnitude of length, area, volume, mass is important.