1. A carton of eggs rests on the seat of a car moving at 20 m/s. What is the lea

Question

1. A carton of eggs rests on the seat of a car moving at 20 m/s. What is the least distance in which the car can uniformly slow if the eggs are not to slide? The coefficient of static friction between the eggs and the seat is 0.15.

2. A car having a mass of 1,000 kg rounds a curve at a speed of 60 MPH (26 m/s). The curve has a radius of 200 m and is not banked. What is the minimum coefficient of friction required between the tires and the road such that the car does not skid?

3.An outfielder throws a baseball with an initial speed of 20 m/s. An infielder catches the ball at the same level when its speed is reduced to 12 m/s. What work was done in overcoming the resistance of the air if the mass of the ball was .3 kg?

4.A 30 kg child sitting 5.0 m from the center of a merry-go-round has a constant speed of 5.0 m/s.  Assuming only conservative forces are involved, the net work done on the child after making one complete circle on the merry-go-round is what?

Explanation / Answer

1) a = u*g = 0.15*9.8 = 1.47m/s^2

s = 20^2/2a = 400/2.94 = 136m

2) umg = mv^2/R

u = v^2/Rg = 26^2/(200*9.8) = 0.344

3) workdone = loss in KE = 0.5*0.3*(20^2-12^2) = 38.4 J

4) Since net displacement is 0, word done by conservative force = integral (Fds) = 0

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.