Drag

Learning Objectives (a) explain that an object travelling in a fluid experiences a resistive or a frictional force known as drag; (b) state the factors that affect the magnitude of the drag force; (c) determine the acceleration of an object in the presence of drag;

Drag Drag is a resistive force It depends on: velocity cross-sectional area Shape Roughness of surface It also is affected by the density of a gas or viscosity of a liquid

To calculate Drag F = 1/2 ρCdAv2 Where F = drag force ρ = density Cd = coefficient of drag V = velocity

We will take ρ as = 1.29kgm-3 For a rough sphere Cd = 0.48 For a flat plate = 1.28