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Chapter5:Applications of Newton’s laws. Chapter5 newton’s laws. Ex 5-2 To push or to pull a sled?. Friction is less when you pull, since F N is less. Ex5-4 Pulling against friction. m=10kg s =0.3 F N =40N . Ex 5-4 A box against a wall. When mg> F fr = s F N , the box slides down .
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Chapter5:Applications of Newton’s laws Chapter5 newton’s laws
Ex 5-2 To push or to pull a sled? Friction is less when you pull, since FN is less
Ex5-4 Pulling against friction m=10kg s=0.3 FN=40N
Ex 5-4 A box against a wall When mg>Ffr=sFN, the box slides down
Ex 5-6 The skier with friction K=0.01 Winning (acceleration) does not depend on mass!
Dynamics of Uniform Circular Motion Center-seeking Acceleration and Force Frad = m arad
Conical Pendulum Center-seeking Force: Tension Circular Motion
Velocity dependent forces Terminal velocity }=
No Skidding on a Curve (I) Center-seeking Force : Static Friction msmin= ?
No Skidding on a Curve (II) m =1000 kg r = 50.0 m C v = 14.0 m/s
No Skidding on Banked Curve Design Speed Ff : not required FN cosq= m g arad
No Skidding on Banked Curve Overview Notes: • Coordinates x-y • Acceleration +x direction Ff arad
Problem 5-18 Starting point=9.3m up
Problem 5-24 s=0.4 K=0.3 (a) What is min. m before it moves? (b) What is m for moving at v=const.