Question

The CGS unit for measuring the viscosity of a liquid is the poise [P]: 1 P = 1 g/(s·cm). The SI unit is the kg/(s·m). The viscosity of water at 5°C is 2.06 ✕ 10-3 kg/(s·m). Express this viscosity in poise.

Answer 1

`\mu = 2.06 * 10^(-2)  P`

Step-by-step explanation:

We have that
`1\, P = 1 \, (g)/(s\,cm)`

if the viscosity of water at 5°C is:

`\mu = 2.06 * 10^(-3) (kg)/(s\cdot m)`

To express this quantity in poise, we have to go from SI units to CGS units, we can do that by replacing kilograms by grams and meters by centimeters.

we know that:

`1\, kg = 1000\, g\\\\1\,m = 100 \, cm`

Inserting this into the preceding equation we have:

`\mu = 2.06 * 10^(-3) (kg)/(s\cdot m)= 2.06 * 10^(-3) (1000)/(100) (g)/(s\cdot cm)\\\mu = 2.06 * 10^(-2) (g)/(s\cdot cm) = 2.06 * 10^(-2) P\\\mu = 2.06\,c P`

Where
`cP` or centipoise is a hundredth of a poise