PHYS 205 Midterm: PHYS 206 TAMU Exam3 2007
Physics 218: Mechanics Exam 3, 20 November 2007
Print your name neatly:
Last name:
First name:
Sign your name:
Your instructor: Your section:
Please fill in your Student ID number (UIN): – –
IMPORTANT
Read these directions carefully:
•There are 4 problems totalling 100 points. Check your exam to make sure you have all
the pages. Work each problem on the page the problem is on. You may use the back.
If you need extra pages, I have plenty up front.
•Each problem with its associated figure is self explanatory. If you must ask a question,
then come to the front, being as discrete as possible so as not to disturb others.
•Indicate what you are doing! We cannot give full credit for merely writing down
the answer. Neatness counts! I will give generous partial credit if I can tell that you
are on the right track. This means you must be neat and organized.
•There is potentially useful information on the last page. Do not waste time on complex
algebra or arithmetic.
Grading:
Problem 1 Problem 2 Problem 3 Problem 4 TOTAL
1a. (20 points) Derive the expressions for the ~
irand ~
iθcomponents of the velocity and
acceleration.
1b. (5 points) An object of mass mis moving in the x, y plane. Its position varies with
time so that a vector from the origin to the object has a length given by kt2where k
is a known constant and tis the time in seconds. The vector points at an angle with
the xaxis that varies according to bt2where bis a known constant.
What is the force, as a function of time, acting on the object?
Document Summary
Physics 218: mechanics exam 3, 20 november 2007. Please ll in your student id number (uin): Read these directions carefully: there are 4 problems totalling 100 points. Check your exam to make sure you have all the pages. Work each problem on the page the problem is on. If you need extra pages, i have plenty up front: each problem with its associated gure is self explanatory. If you must ask a question, then come to the front, being as discrete as possible so as not to disturb others: indicate what you are doing! We cannot give full credit for merely writing down the answer. I will give generous partial credit if i can tell that you are on the right track. This means you must be neat and organized: there is potentially useful information on the last page. Do not waste time on complex algebra or arithmetic.
