Page 1 - Lesson Notes - Fluid Friction

SAI INTERNATIONAL SCHOOL
Class8
Lesson Notes
Subject-Physics
CH-Friction
Subtopic-Fluid Friction

Fluid friction is the force of friction exerted by liquids and gases on objects moving
through them.
fluid friction is also called drag.

Streamline shape: Special shape given to the objects moving with high velocity in the
fluid to reduce fluid friction.
1) Birds flying in air have streamline shape which reduces fluid friction.
2) Fishes moving in water have streamline shape.
3) Submarines and air crafts moving with high speed in water and air
respectively are given streamline shape to reduce friction.

Factor affecting fluid friction:
1) Speed of object inside the fluid: As the speed of object increases fluid
friction experienced also increases.
2) Shape of the object: Streamlined shaped object experience less fluid
friction.
3) Viscosity of the fluid: As the viscosity of fluid increases fluid friction also
increases.