Physics 101 - Homework 6

Instructions: Complete this form and click submit. The answers will be posted on the course home page after the due date and before the next exam. If you want to change any of your answers after you click submit, then go back and give your answers again and click submit.

Your Name: e.g. John Doe
Your Campus ID: e.g. 12345678
Your SFA Email Address: e.g. doejd@titan.sfasu.edu
Due Date 11/8/2007 5:00PM

0. Some of the questions below have been modified from the in-class handout to test your understanding of the material. Try to answer these first without looking at the handout, then study the handout, modify your answers if necessary and click Submit.

I understand
I do not understand

1. A projectile fired at 60o will hit the ground at the same place as a projectile fired with the same initial speed at an angle of

(a) 30
(b) 45
(c) 90
(d) 15

2. Fred drops a stone down a well and sees it hit the water 2 seconds later. How deep is this well? (Neglect air resistance.)

(a) 9.8 m
(b) 19.6m
(c) 4.9m
(d) 78.4 m
(e) 29.4m

3. What kind of path will an object follow if there are no external forces except for gravity acting on it?

(a) circular
(b) straight line
(c) curved
(d) parabolic
(e) elliptical

4. What kind of path will an object follow if there are no external forces (not even gravity) acting on it?

(a) circular
(b) straight line
(c) curved
(d) parabolic
(e) elliptical

5. When air resistance is negligible in projectile motion, what projection angle will give the maximum range?

(a) 0o
(b) 30o
(c) 60o
(d) 45o
(e) 90o

6. A gun five feet above the ground fires a bullet (A) in a horizontal direction. As bullet (A) leaves the gun a second bullet (B) is dropped from the end of the gun. Which bullet reaches the ground first? (Neglect air resistance.)

(a) A
(b) B
(c) neither of these

7. The net force acting on a body traveling at constant velocity in a circle is zero.

(a) True
(b) False

8. Suppose you drop a flare from an airplane traveling at a constant speed, and further suppose that air resistance doesn't affect the falling object. What will be its falling path as observed by someone at rest on the ground, not directly below but off to the side where a clear view can be seen?

(a) the flare will fall straight down until it hits the ground
(b) the flare will travel diagonally in a straight line directly below the plane until it hits the ground
(c) the flare will travel in a parabolic path directly below the plane until it hits the ground

9. A Mack truck and a Volkswagen have a head-on collision. Upon which vehicle is the weaker impact force?

(a) Mack truck
(b) Volkswagen
(c) both experience identical impact forces

Need more examples or assistance?  If you have a new text book then you may be able to access tutorials and online quizes at www.PhysicsPlace.com.  The Access Code for this site is normally included in the first few pages of the book. See Dr. B for help during these office hours.