a roller coaster car moves along with the frictionless track shown in the diagram below. Use the information given on the diagram to answer the questions. the mass of the roller coaster car is 800 kg. assume the roller coaster comes to the rest at point a before moving down the hill. approximate the value for the acceleration due to gravity gas 9.8m/s^2. how high is point A above the ground?show work.

True or false: the cycle of seasons on the earth is caused by the tilt of the earth on its axis toward and away from the sun.

1. jay fills a wagon with sand (about 20 kg) and pulls it with a rope 30 m along the beach. he holds the rope 25° above the horizontal. the rope exerts a 20-n tension force on the wagon. how much work does the rope do on the wagon?

The great sandini is a 60.0-kg circus performer who is shot from a cannon (actually a spring gun). you don’t find many men of his caliber, so you him design a new gun. this new gun has a very large spring with a very small mass and a force constant of 1100 n/m that he will compress with a force of 4400 n. the inside of the gun barrel is coated with teflon, so the average friction force will be only 40.0 n during the 4.00 m he moves in the barrel. at what speed will he emerge from the end of the barrel, 2.50 m above his initial rest position?