Chapter 1: Fundamentals Workout problems 1. A person is strolling around a circular park of 100 feet diameter. He makes a full circle and comes back to the same point. What is the actual distance traveled by the person? 2. What is the average velocity of my car if I travel 200 feet in 12 sec? 3. What is the work done in pushing a box weighing 100 lb by 25 ft? 4. How much power is needed to raise a 3 Ton elevator 50 feet in 60 sec? 5. What is the horsepower in number 3? 6. What is the torque if a force of 15 lbs is applied to the end of a lever arm 5 feet from the pivot point? 7. How much torque does a 10 HP motor deliver at 1800 RPM? What about 1200 RPM? 8. An elevator is hoisted by its cable at constant speed. What is the work done on the elevator? 9. For a constant force in the direction of displacement, so that W = F.d, how much can twice the work be done by a force of half the magnitude? 10. An automobile jack is used to lift a heavy car by exerting a force that is much smaller in magnitude than the weight of the car. Does this mean that less work is done on the car by the force exerted by the jack than if the car had been lifted directly? Explain. 11. Does the kinetic energy of a car change more when it speeds up from 10 to 15 m/s or from 15 to 20 m/s? Explain. 12. When a constant force is applied to a body moving with constant acceleration, is the power of the force constant? If not, how would the force have to vary with speed, for the power to be constant?
13. A car accelerates from an initial speed to a greater final speed while the engine delivers constant power. Is the acceleration greater at the beginning of the process or at the end? Explain. 14. Describe and explain the difference between Brake HorsePower (BHP), Indicated Horse Power (IHP) and Actual HorsePower.