You are told that there are four forces acting on an object. The forces do +60 J, -30 J, -20 J and 0 J of work on the object. Based on the work-energy theorem in Section 6.2, what happens to the speed of the object?
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If the force on an object does negative work, which of the following is always true? The force is acting to the left The force is in the opposite direction as the motion The force is acting to the right The force is slowing the object down An engine is used to pull the coaster from rest to the necessary speed on the launch track by doing 10,000,000 J of work through the 150m launch track distance. Assuming no energy is lost to friction, how much kinetic energy does the engine supply to the coaster during the launch track distance? 100,000J 10,000,000J 1,000,000J 100,000,000J What is the speed of the coaster just as it launches upward if the mass of the cart and passengers is 6000kg? 58m/s 46m/s 3300m/s 10m/s 16,667 m/s
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