This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: hernandez (ejh742) – oldhomework 24 – Turner – (58120) 1 This printout should have 13 questions. Multiplechoice questions may continue on the next column or page – find all choices before answering. 001 10.0 points A circular disk, a ring, and a square have the same mass M and width 2 r . disk 2 r ring 2 r square 2 r For the moment of inertia about their cen ter of mass about an axis perpendicular to the plane of the paper, which statement concern ing their moments of inertia is true? 1. I square > I ring > I disk correct 2. I disk > I square > I ring 3. I square > I disk > I ring 4. I ring > I square > I disk 5. I ring > I disk > I square 6. I disk > I ring > I square Explanation: In the ring, the same mass of the disk is concentrated at the maximum distance from the axis, so I ring > I disk . In the square, the same mass of the ring lies at distances which are between r and r √ 2 ( at least the radius of the ring), so I square > I ring and I square > I ring > I disk . 002 (part 1 of 2) 10.0 points Two particles move in opposite directions along a straight line. Particle 1 of mass m 1 = 21 kg at x 1 = 25 m moves with a speed v 1 = 48 m / s (to the right), while the particle 2 of mass m 2 = 50 kg at x 2 = − 23 m moves with a speed v 2 = − 44 m / s (to the left). Given: Counterclockwise is the positive angular direction. d 1 m 1 m 2 x 2 x 1 v 1 v 2 d 2 A B x y What is the total angular momentum of the system about the zaxis relative to point A along y axis if d 1 = 17 m? Correct answer: 20264 kg m 2 / s. Explanation: The angular momentum along z axis is given by L = r p sin θ , where p is the total linear momentum. We find that p = m 1 v 1 + m 2 v 2 , where v 2 is negative. Since at pointis negative....
View
Full
Document
This note was uploaded on 06/14/2011 for the course PHY 303K taught by Professor Turner during the Spring '08 term at University of Texas.
 Spring '08
 Turner
 Physics, Work

Click to edit the document details