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spartankaboos

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1) A box weighing 210 N is pushed up an incline plane that is 3.0 meters long. A force of 140 N is required. If the box is lifted 1.0 m, what is the efficiency of the inclined plane?

2) A figure skater with arms drawn spins on the ice at a rate of 5.0 rad/s and has a moment of inertia of 1.875 kg*m^2 . What is the angular momentum of the skater?

3) A 1,500kg truck moving at 15 m/s strikes a 750 kg automobile stopped at a traffic light the vehicle. The vehicles hook bumpers and skid together at 10 m/s. What is the decrease in kinetic energy?

4) A uniform bridge span weighs 50,000 N is 40 m long. An automobile weighing 15,000 N is parked with its center of gravity located 12 m from the right pier. What upward support force is provided by the left pier?

5) A 61 kg student sits at a desk 1.25m away from a 70 kg student. What is the magnitude of the gravitational force between the two students?

6) A tire has an initial angular velocity of 8∏ (pi) rad/s and slows at a rate of 2 rad/s. What is the angular displacement as it comes to a stop?

7) A rubber stopper of mass m2 = 0.020 kg is tied to a string an allowed to revolve in a circle of radius of 0.95 m. There is a mass of m1 = 1.00 kg hanging from the bottom providing a centripetal force. Calculate the linear (tangential) speed of the rubber stopper.

8) A rollercoaster car speeds up and down a hill past points a, b, and c as shown. The car has a mass of 500 kg and a speed of 25.0 m/s at point B where the track radius is 10 m. A: What is the maximum speed the car can have at point c, radius 19.6 m, for the gravitational force to hold it on the track? Use g = 10.0 m/s^2

9) On the planet Xenos, an astronaut observes that a seconds pendulum with a mass of 2.0 kg and a length of 1.216m oscillates with a period of 2.00 seconds. What is the free-fall acceleration on the planet xenos?