PHYSICS 1403 Quiz 3, February 1, 2008
This should be TRIVAL, if you were in class Wed. &/or if you’ve studied Ch 3 & at least started Ch. 4!
Please write NEATLY & LARGE ENOUGH for me to read! Thanks.
(Use back if necessary. Please tell me you’ve done so!)
Name: ______________________
1. Wed., Jan. 30, near the end of the Projectile discussion, I did a DEMONSTRATION designed to
illustrate some simple physics. (If you were in class Wed., you likely will be able to answer this. If you “cut”
class that day, as many of you are already in the habit of doing, you probably won’t be able to!)
2.
a.
(3 points) Briefly describe this demonstration & tell me briefly what physical point I was trying to
make by doing it.
b.
(3 points) This demonstration was similar to an example in the text. Briefly tell me what this
example is about.
See figure. A ball is thrown horizontally with initial velocity v0 = 20 m/s, from the roof of
a building a height h = 50 m tall. It lands on the ground, a distance d from the base of the
building. (Hint: A ball thrown horizontally has no initial vertical velocity component! vy0 = 0 because θ0 = 0!)
a. (5 points) Calculate the time it takes the ball to hit the ground.
v0
O
h

y
b.
3.
x
d
(5 points) Calculate the horizontal distance d from the base of the building at which the ball lands.
(4 points) (Note: Zero Credit will be given for answering the following using only the word “Physics”!) I
asked you (by email, orally, & in writing) to read Ch. 4. Briefly tell me what the main topic of Ch. 4 is.
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