A boy is trying to roll a bowing ball up a hill as shown in the image below. If friction is ignored what is the minimum initial velocity that the ball must have for it to reach the top of the hill? (Recall that g=9.8 m/s^2)
A.14 m/s
B.21 m/s
C.28 m/s
D.7 m/s

Aspecial electronic sensor is embedded in the seat of a car that takes riders around a circular loop-the-loop ride at an amusement park. the sensor measures the magnitude of the normal force that the seat exerts on a rider. the loop-the-loop ride is in the vertical plane and its radius is 23 m. sitting on the seat before the ride starts, a rider is level and stationary, and the electronic sensor reads 740 n. at the top of the loop, the rider is upside down and moving, and the sensor reads 370 n. what is the speed of the rider at the top of the loop?

Aspring with a mass of 2 kg has a damping constant 14 kg/s. a force of 3.6 n is required to keep the spring stretched 0.3 m beyond its natural length. the spring is stretched 0.6 m beyond its natural length and then released. find the position of the mass at any time t. (assume that movement to the right is the positive x-direction and the spring is attached to a wall at the left end.)

An initially unpolarized light if intensity 500 w/m^2 passes through four polarizers. the transmission axis between adjacent polarizers is 45∘. what percentage of the initial intensity is transmitted by the system?