A car drives straight down toward the bottom of a valley and up the other side on a road whose bottom has a radius of curvature of 115 m. At the very bottom, the normal force on the driver is twice his weight. At what speed was the car traveling? O 63.3 m/s O 63.9 m/s O 39.6 m/s O 33.6 m/s

5. A railway curve has a radius of 420 m the rails are 1.5m apart and the outer rail is elevated at 15 cm at what max speed will there be no lateral pressure on the wheels in mph.

3. Determine if the tractor which has a weight of 8000 lb with center of gravity at G, can push the 550-lb log up the incline. The coefficient of static friction between the log and the ground is 0.5, and between the rear wheels of the tractor and the ground 0.8. The front wheels are free to roll. Assume the engine can develop enough torque to cause the rear wheels to slip. 1.25 ft B 2.5 ft |10° 3 ft -7 ft

A student releases a system on an incline as shown. The coefficient of friction of static friction between the 20kg box and the surface is 0.28 and the coefficient of kinetic friction is 0.16. Neglect drag. What is the magnitude of maximum static friction between the block and the surface in this situation? 47.1 What direction is the friction on the 20kg block? up-left What direction will the 20kg block slide? 20kg 7.6kg neither What is the magnitude of the friction? 26.5 What is the magnitude of the net force on the system? 0. What is the magnitude of the system's acceleration? 0.015 m/s? What is the tension in the string? 74.6 cannot be de check answers nallenge ne Calculator und = 343m/s ant figures