Kinesiology 2241A/B Lecture Notes - Lecture 26: Relative Velocity, Mattress, Boundary Layer

• School: Western University
• Department: Kinesiology
• Course: Kinesiology 2241A/B
• Professor: Thomas Richard Jenkyn

Document Summary

When we move through a uid, there"s a drag force: e. g. Think drafting in cycling - the rst guy splits the air and behind him is a wake. The energy of the wake is created by him in the form of splitting air: the person drafting behind them is basically dragging them forward. In the real world: we throw projectiles through air. Air is a uid, and therefore imparts a drag force to the projectile that is equal to the speed squared. Headwind: v isn"t how fast you cross the ground, its how fast the air moves past relative to you, headwind increases the relative speed, you experience that much more drag. Tail wind: take the 20 you want to go forward, and the 5 of the tailwind, the relative speed going across the body is only 15. Drag force can slow you down in the example of a parachute. Direction of the velocity changes with its parabolic path.