qz4sol_3695sp10 - potential energy is U A = 10 J. Thus the...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
TA: Tomoyuki Nakayama Tuesday, February 16 th , 2010 PHY 2048: Physic 1, Discussion Section 3695 Quiz 4 (Homework Set #6) Name: UFID: Formula sheets are not allowed. Calculators are allowed. Do not store equations in your calculator. You need to show all of your work for full credit. ________________________________________________________________________________ The figure below right shows a plot of potential energy U versus position x of a 0.400-kg particle that can travel only along an x axis under the influence of a conservative force. The graph has these values: U A = 10.0 J, U C = 22.0 J and U D = 27.0 J. The particle is released at the point where U forms a “potential hill” of “height” U B = 14.0 J, with kinetic energy of 5.00 J. a) What is the speed of the particle at x = 3.5 m? The initial mechanical energy of the particle is E i = K i + U i = 5 + 14 = 19.0 J Since only a conservative force is exerted on the particle, its mechanical energy is conserved. At x = 3.5 m, the
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: potential energy is U A = 10 J. Thus the kinetic energy is E = K + U K (x = 3.5) = E U A = 19 10 = 9.00 J The definition of kinetic energy yields K = (1/2)mv 2 v = (2K/m) = 6.71 m/s b) What is the position of the turning point on the right side? The particle turns around when its kinetic energy is zero. The kinetic energy is zero when the potential energy equals the mechanical energy. The potential energy function between x = 7 m and x = 8 m is given by U = [(U D 0) /(7-6)] (x-7) = 27(x-7) The function takes the value of E = 19 J at 19 = 27(x-7) x = 19/27 + 7 = 7.70 m c) What is the position of the turning point on the left side? The potential energy function between x = 1 m and x = 3 m is expressed as U = [(U A- U C )/(3-1)](x-1) + U C U = -6(x - 1) + 22 The function takes the value of E = 19 J at 19 = -6(x-1) + 22 x = (19 - 22)/(- 6) +1 = 1.50 m...
View Full Document

This note was uploaded on 01/15/2012 for the course PHY 2048 taught by Professor Field during the Fall '08 term at University of Florida.

Ask a homework question - tutors are online