Cornell University

PHYS 1112

References: Chap. 6, section 6.4; Chap. 13, section 13.3-4 Lecture notes on Automotive Power, Wind Power, & Hydropower Chap. 8, intro., sections 8.1-3 Physics Ideas: Gravitational potential energy for Universal Gravitation Power Momentum, Impulse, & Conservation of Momentum Math Skills: Vector Dot Product Path Integrals Geometry, Trigonometry, Algebra, Calculus Vector Geometry, Algebra, & Components Learning Goals: (Be sure you understand where and how each goal in each assignment applies to our homework, discussion, lecture, and lab activities.) * Define power, and calculate it in mechanical systems. * Define momentum and impulse, and relate them to instantaneous & average force. * Calculate momentum, momentum changes, & impulse, and use them in conjunction with the principle of Conservation of Momentum. * Show that algebraic & numerical results have correct units and are physically reasonable. For extra practice: Chapter 6: Qs #Q6.17-22; Es & Ps #6.47, 85, 89 (not turned in Chapter 13: Qs #Q13.11, 13, 15; E's & Ps #17 or quizzed) Chapter 8: Qs #Q8.2-13, 15, 17, 19, 20, 23-25 Es & Ps #8.1, 3, 5, 7, 13, 30, 33, 37, 41, 43, 73, 87, 99 #6.55 [Ski Tow Power] Draw a diagram to illustrate the geometry and your reasoning. #13.51 [Escape Speed] #13.69 [Orbit Energies] #8.68 [Railroad Handcar] [HINTS: It's important to recognize whether each velocity is specified relative to the cart or the ground and to distinguish between the reference frame of the cart before vs. after the mass is thrown. These are different if the cart's speed changes during the throw.] Please add: (d) In part (a), what is the velocity (speed & direction) of the thrown mass relative to the ground? How and why would the results of part (a) change if instead the mass were thrown out of the cart with a velocity of 2.00 m/s sideways relative to the ground? How would the throwing action be different as seen by someone riding on the cart? [Assignment CONTINUES on the next page.]