How fast would you need to fire a 80 g Hot Wheels car down a straight track in order for it to successfully coast through a circular vertical loop of track with a radius of 30 cm? Draw a diagram and construct a force balance to determine your answer?

A roller coster has a loop with 7.62 diameter. a) What is the minimum height above the bottom of the loop required to acheive enough speed so that the coaster does not loose contact with the track? b) How many g's does the passenger expirience at the top of the loop AND at the bottom of the loop upon entering the loop.? c) suppose the coaster came to rest at 3/4 h on the other side of the loop. What fraction of the energy was lost?

- Question Completion Status: QUESTION 5 A 0.7-kg ball is thrown with a speed of 14.5 m/s at an angle 38.7 degrees. What is its speed at the highest point? Hint: V= +v QUESTION 6

A net external force is applied to a 25-kg object that is initially moving at 1 m/s. The net force component along the displacement of the object varies with the magnitude of the displacement as shown in the drawing.   What is the final KE (in Joules) of the object at x=20m?   What is the speed (in m/s) of the object at x=20m?

A 4 kg box starts up a 30° incline with 128J of kinetic energy. How far will it slide up the incline if the coefficient of kinetic friction between the box and incline is 0.30?

In a truck-loading station at a post office, a small 0.48 kg package is released from rest at point A on a track that is 1/4 of a circle with radius 2.2 m (as shown in the below Figure). The size of the package is much less than 2.2 m, so the package can be treated as a particle. It slides down the track and reaches point B with a speed of 3.5 m/s. From point B, it slides on a level surface a distance of 4.9 m to point C, where it comes to rest. m A R K B d (a) How much work (in J) is done on the package by friction as it slides down the circular arc from A to B? (b) What is the coefficient of kinetic friction on the horizontal surface?

An energy storage system based on a flywheel (a rotating disk) can store a maximum of 4.0 MJ when the flywheel is rotating at 20,000 revolutions per minute. What is the moment of inertia of the flywheel?

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A 1400 kg car delivers a constant 42 hp to the drive wheels. We assume the car is traveling on a level road and that all frictional forces may be ignored.A) What is the acceleration of this car when its speed is 10 m/s?B) If the speed of the car is doubled, does its acceleration increase, decrease, or stay the same? Explain

A 50 kg box slides down a 6-meter high plane angled 30o to the horizontal. If the coefficient of friction force between the box and the plane is 0.4 what is the speed of the box at the end of the plane?