exam 2 spring 2009

# exam 2 spring 2009 - QUESTION 1* The Work Kinetic-Energy...

This preview shows pages 1–3. Sign up to view the full content.

QUESTION 1** The Work Kinetic-Energy Theorem is invalid if work is done by a non- conservative force. (T) True (F) False QUESTION 2** This and the next question refer to the following situation: A small block having a mass 0.1 kg starts at rest at the top of a frictionless track a height 1.7 m above the horizontal floor. It slides down the track and then around a loop-the-loop having a diameter of 0.6 m. What is the normal force exerted by the track on the small block as it goes around the top of the loop? (a) 6.2 N (b) 5.6 N (c) 4.9 N (d) 3.8 N (e) 2.4 N QUESTION 3* After rounding the loop the block continues along the frictionless horizontal floor, running into the end of a horizontal spring whose other end is fixed. If the spring is compressed a distance of 0.05 m from its resting length as the block is (momentarily) brought to rest, what is the spring constant? (a) 6.6 × 10 2 N/m (b) 8.6 × 10 2 N/m (c) 1.3 × 10 3 N/m (d) 1.8 × 10 3 N/m (e) 2.7 × 10 3 N/m QUESTION 4* A block of mass M is initially at rest on a horizontal, frictionless table. A bullet of mass m is fired from the left with an initial horizontal speed v 0 toward the block, as shown in the upper

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

View Full Document
becomes lodged inside it. After the block and bullet start moving to the right, a second bullet of mass m is now fired horizontally from the right with an initial speed v 0 toward the block. The second bullet hits the block and becomes lodged inside it. Which one of the following describes the motion of the block after both bullets are lodged inside it? (a) The final velocity is to the left. (b) The final velocity is zero. (c) The final velocity is to the right. QUESTION 5** A pendulum is released from rest, as shown in Figure A. When the bob is directly below the pivot point, the ideal string encounters an ideal peg, about which it begins to wrap, as shown in Figures B and C. The peg is higher than the initial height of the pendulum. In Figure C, the bob rises up to a height (a) equal to the original height of the bob in Figure A. (b) greater than the original height of the bob in Figure A.
This is the end of the preview. Sign up to access the rest of the document.

## exam 2 spring 2009 - QUESTION 1* The Work Kinetic-Energy...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online