Physics 211, Homework Set #6

These problems are due Wednesday, April 21, at 5 PM. You may place your solutions in the mailbox outside my office door, or bring them into class.

The grading scheme for the homework set is as follows: three of the problems will be chosen to count for 10 points, and you may be given partial credit on them. You will receive 1 point for at least attempting each of the other questions. However, you do not know which of the questions will be chosen for detailed grading ... and therefore you should do them all.

Cutnell and Johnson, Chap 7, problem 3
Cutnell and Johnson, Chap 7, problem 9
Cutnell and Johnson, Chap 7, problem 13
Cutnell and Johnson, Chap 7, problem 19
Cutnell and Johnson, Chap 7, problem 41
Cutnell and Johnson, Chap 7, problem 48
Saga of the Gun and Block
Cutnell and Johnson, Chap 7, problem 31
Cutnell and Johnson, Chap 7, problem 35
Cutnell and Johnson, Chap 7, problem 56
Jerome Bettis, a running back for the Pittsburgh Steelers, grabs a swing pass in the flat and runs downfield toward the goal line at 18 miles per hour.
Linebacker Zach Thomas of the Miami Dolphins tries to stop him. Starting from the back of the end zone (he was covering the tight end), he runs forward at 13 miles per hour to tackle Bettis.
The two players meet head-on at the goal line. Thomas wraps his arms around Bettis, so that they move together as a single unit. The ground is so slippery at the goal line that neither can find any traction.
- What is the mass of each player?
- What is the momentum of each player before the collision?
- Which way do the two players move after the collision?
- How fast do they move?
- Assume the collision took about 0.05 seconds. How large a force does Bettis exert on Thomas?
- How does the acceleration experienced by Thomas compare to the acceleration due to the earth's gravity? In other words, how many "gees" does Thomas endure?

This page maintained by Michael Richmond. Last modified Mar 8, 1999.