ملتقى الفيزيائيين العرب - مساعده في Circular Motion

السلام عليكم ورحمة الله وبركاته

آرجو المسآعده في حل هذه المسآلتين من جابتر Circular Motion

Problem 1:- A car is driven at constant speed over a circular hill and then into a circular vally with the same radius, R= 10m. At the top of the hill, the normal force on the driver from the car seat is 0. The driver's mass is 70 kg. Determine

1. the car speed
2. the magnitude of the normal force on the driver from the seat when the car passes through the bottom of the valley

http://www11.0zz0.com/2013/04/30/17/523886615.jpg

Problem2:- A car initially traveling eastward turns north by traveling in a circular path at uniform speed as in the figure below. The length of the arc ABC is 253m, and the car completes the turn in40 -s.
(a) What is the acceleration when the car is at B located at an angle of 30? Express your answer in terms of the unit vectors ˆi and ˆj. Determine (b) the car's average speed and (c) its average acceleration during the 40-s interval

http://www11.0zz0.com/2013/04/30/17/634564184.jpg

شكرآ :)