An apple is in mid-air, falling down. We know its weight (mg) is a force pulling the apple down. According to Newton's Third Law (the law of action and reaction), there must be another force equal and opposite to the apple's weight.
a) What is this other force?
b) What type of friction, kinetic or static, keeps a car from skidding out of a turn>
c) Which conversation law explains why is it harder to move a fidget spinner that is spinning than one that isn't spinning, why an ice skater spins faster when she pulls her arms in close to her body, and why a planet moves faster in its orbit when it is closer to the sun?
a] Force of attraction of Earth towards apple.
b] static friction prevents skidding
c] conversation of angular momentum.
It is because angular momentum(L)has to be conserved. When he pulls his arm, moment of inertia (I) decreases, so angular velocity(w) must increase as L=Iw
An apple is in mid-air, falling down. We know its weight (mg) is a force pulling...