Share B2.1.2 - B2.1.4
Save to Folder
What is Newton's First Law?
Law of inertia - an object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction, unless acted upon by an
What is Newton's 2nd law?
Law of motion/acceleration - force is equal to mass multiplied by acceleration - the acceleration of an object is directly proportional to the net force acting
What is Newton's 3rd law?
Law of reaction - for every action there is an equal and opposite reaction
what does the term collision mean?
when two or more objects come into contact with (exert forces on) each other during a short period of time.
what is the equation for coefficient of restitution?
relative velocity after collision / relative velocity before collision
what factors influence the coefficient of restitution?
material of objects, height of drop
give a legal example of CoR use in sport
squash ball warm up - ball travels faster when it is warm
Give an illegal use of CoR in sport
Freezing of baseballs / bats CoR is limited
How is the CoR use controlled in sport - give an example
New tennis / table tennis balls in matches; table tennis balls / basketball checked and must bounce to a certain height; golf club / baseball bats limit CoR
Define friction
“A force that acts parallel to the interface of two surfaces that are in contact, and opposes their relative motion”
What is the equation for friction force?
f = coefficient friction N (or R)
What does the coefficient of friction mean?
nature of the 2 surfaces in contact with each other - how slippy or rough they are
What factors influence amount of friction in sport?
nature of footwear and the surfaces , reaction forces - e.g weight
what sport would you want a low CoF and why?
ice skating / skiing - to maximise speed and fluency over ice/snow
What sport would you want a high CoF and why?
spikes / studs - increase grip
what does static friction relate to?
refers to the force acting between two surfaces that are not moving relative to each other
