pex2sm08 - August 4, 2008 PHY 2053 Discussion Practice Exam...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
August 4, 2008 PHY 2053 Discussion Practice Exam 2 (Chapter 6-8) 1. A crane drops a 0.30 kg steel ball onto a steel plate. The ball’s speeds just before impact and after are 4.5 m/s and 4.2 m/s respectively. If the ball is in contact with the plate for 0.030 s, what is the magnitude of the average force that the ball exerts on the plate during impact? (Impulse-Momentum Theorem) a. 87 N b. 133 N c. 3.0 N d. 3.5 N 2. A machine gun is attached to a railroad flatcar that rolls with negligible friction. If the railroad car has a mass of 6.25 × 10 4 kg, how many bullets of mass 25 g would have to be fired at 250 m/s off the back to give the railroad car a forward velocity of 0.5 m/s? (Conservation of Momentum) a. 400 b. 2 000 c. 3 000 d. 5 000 3. In a two-body collision, if the kinetic energy of the system is conserved, then which of the following best describes the momentum after the collision? (Collisions) a. must be less b. must also be conserved c. may also be conserved d. is doubled in value 4. A 20-kg object sitting at rest is struck elastically in a head-on collision with a 10-kg object initially moving at +3.0 m/s. Find the final velocity of the 20-kg object after the collision. (Elastic Collisions)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 12/13/2011 for the course PHY 2053 taught by Professor Buchler during the Fall '06 term at University of Florida.

Page1 / 2

pex2sm08 - August 4, 2008 PHY 2053 Discussion Practice Exam...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online