2. A gold sol solution with a particle mass concentration of 5•10-5 kg/m3 was examined under an ultramicroscope. The average number of particles in a field of view with an area of 1•10-6 m2 and a beam depth of 2•10-6 m is 65. Assuming that the gold sol particles are spherical, calculate their average radius. The density of gold is 19.6•103 kg/m3.

If the file does not open for you, install the Rar archiver program. Inside the archive, the solution is in WORD format.