# viscosity

## viscosity races

The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal concept of "thickness". For example, honey has a much higher viscosity than water.

Viscosity is a property arising from collisions between neighboring particles in a fluid that are moving at different velocities. When the fluid is forced through a tube, the particles which comprise the fluid generally move more quickly near the tube's axis and more slowly near its walls: therefore some stress, (such as a pressure difference between the two ends of the tube), is needed to overcome the friction between particle layers to keep the fluid moving. For the same velocity pattern, the stress required is proportional to the fluid's viscosity.

## what you need

A stop watch

A tape measure

A ramp

Small containers

Pencils

Recording tables

A plastic drop cloth

## method

1. Measure 30 mls of each liquid.

2. Set your stop watch to 0

3.

Tip 1 liquid at a time from the top of the ramp remember to communicate with your group to ensure the timer starts as you tip the lquid.

4. Let the liquid flow for the set time you have decided and measure the distance travelled.

5. Record your results in the table.

6. Repeat for each type of liquid recording your results as you go.

7. Clean your ramp for the next test.

8. Tip one liquid on the ramp and time how long it takes to reach the bottom.

9. Record your results in the table.

10. Repeat for each time of liquid recording your results as u go.

11. Record each groups results as thay become avaliable.

12. Using the calculator determine the main distance for each liquid.