IB SEHS HL Topic 10. Friction and Drag
Terms in this set (7)
10.1.1 Describe friction
A force that acts parallel to the interface of two surfaces that are in contact, and opposes their relative motion.
F=μR, where the μ is the coefficient of friction and R is the normal reaction force
10.1.2 Describe the coefficient of friction
Is a dimensionless scalar quantity which is the ratio of the force of friction, F between two bodies and the normal reaction force, R
The magnitude of the coefficient of friction depends on the materials in contact.
The greater the interaction between the molecules of the interfacing surfaces, the greater the size of the coefficient of friction. (greater the surface area, the greater the coefficient of friction)
Coefficients of friction range in value between zero and one, but can sometimes be higher.
10.1.3 Distinguish between coefficient of static friction and dynamic friction
static: force applied to a stationary object
dynamic: force in an object in motion
Coefficient of dynamic friction is lower than the coefficient of static friction
10.1.5 Define drag
Drag is the force or forces acting to oppose the motion of an object through a fluid medium such as air or water.
10.1.6 Outline different types of drag that can be found in a variety of sporting environments
as a body moves through a fluid, its outer surface catches a layer of the fluid nearby, slowing it down compared to the fluid further away and so causing drag. This can be minimised by changing the surface to reduce the interaction between surface and fluid.
it is caused when air or water molecules are in direct contact with a specific area, in which the nature of the surface directly affects the drag.
This is useful in sports, specifically swimming, because it helps them increase the speed to the max which they can (e.g swim caps, speedo shorts and shaving hair to increase smoothness).
As a body pushes against a fluid, the fluid pushes back (action and reaction). By streamlining the body and minimising the surface area facing the direction of the motion, this type of drag is reduced.
Adjustment of positioning to increase aerodynamics
It can change the way a person/object moves to allow for better performance E.g - cyclists adopting a low profile position, Sprinting form (running)
When a body moves along the surface fluid (usually water) some fluid displaced to form a wave. These waves cause additional forces that oppose motion. Wave drag can be reduced by avoiding motion at the interface between air and water.
Wave drag develops when a swimmer is moving quickly across the top of a body of water, creating waves. These waves cause imbalances in pressure on the body and can limit how fast a swimmer can move.
Wave drag should be decreased as it leads to a decrease in speed of swimmers for example. (stay underwater longer to reduce wave drag)
10.1.7 Discuss factors that influence the amount of drag in sports
- Influence of fluid viscosity, surface size, shape, texture, and relative velocity on drag.
Compare the 'olden days' to now.
How has clothing/equipment/technique/body position changed over the years?
10.1.8 Annotate a free-body diagram showing the direction of relevant forces acting on an athlete or object in sports
YOU MIGHT ALSO LIKE...
MCAT | Mometrix Comprehensive Guide
Fluid Mechanics Chapter 8
KINES 116 FINAL
OTHER SETS BY THIS CREATOR
IB SEHS Topic 3.3 Energy production - Review
IB SEHS SL Option B - Sports Psychology
IB SEHS Option B - SL/HL Sports Psychology
IB SEHS HL Topic 12: Genetics and Athletic Performance
THIS SET IS OFTEN IN FOLDERS WITH...
IB SEHS HL Topic 11: Skill Acquisition and Analysis
IB SEHS HL - Topic 13 - Exercise and Immunity
SEHS: Topic 6.3 - Components of Fitness Terms
IB SEHS Topic 6.4 Principles of Training Program Design Terms