Review of SI prefixes + SI prefixes examples with nanometers, kilopascals and femtometers.

Part of a playlist of scientific notation, unit analysis and significant digits:    • Physics I:  scientific notation, unit...  

Review of SI prefixes + SI prefixes examples with nanometers, kilopascals and femtometers.

In this video, we show a chart of all the SI prefixes and give a quick example of writing the power generated by a hydroelectric power plant in megawatts, and why that's better than stating the power output in standard form.

Next, we work an example of converting the wavelength of yellow light from scientific notation into nanometers. In the next example, we state the value of atmospheric pressure in kilopascals (kPa) given the standard form for the pressure of 101,300Pa. In the final example, we are given the diameter of a uranium nucleus as 11.7 fm (femtometers) and we convert the diameter to scientific notation.

In all cases, SI prefixes are used to simplify the presentation of measurements, and the choice of prefix is really a matter of convention. Wavelengths of light near the visible band are traditionally stated in nanometers, pressures near atmospheric pressure are traditionally stated in kilopascals, and nuclear diameters are traditionally stated in femtometers. This keeps the numbers small and eliminates the need for scientific notation or huge strings of zeroes when communicating measured quantities.