EXAM 3 December 4, 1996 PHYS 207
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g = 9.8 m/sec2 | Radius of the earth = 6.38 x 106 m | The mass of the electron is 9.11 x 10-31 kg. |
1. (10 points) Explain how, knowing
x = x0 + v0 t + ( 1 / 2 ) a t2 ,
you can determine both of the equations governing motion under
constant torque. Be sure to state explicitly the relations you
use between linear variables and angular variables.
Diagram:
4. (30 points) A solid cylinder of radius R and mass
M rolls without slipping down a plane inclined at angle
theta. The coefficient of static friction is
mus. What is the maximum value of theta
that permits the cylinder to roll without slipping? The moment of
inertia of a cylinder about its central axis is
Diagram:
Use this page if necessary to continue any of the problems. Be sure to
label the problem number.
Subject: ***Help With Physics Question Requested***
Date: 24 Nov 1996 03:22:01 GMT
From: *************** (************)
Organization: Student
Newsgroups: sci.edu
I have a physics question for all physics students out there,
2 blocks of wood of equal mass are set up an equal distance away from 2 guns.
Each gun contains a bullet of equal mass, one is rubber one is aluminum.
When fired the rubber bullet bounces off the block of wood while the
aluminum bullet imbeds itself in the wood. The bullets both travel at
equal velocities and the surface on which the blocks sit is ice so
friction is minimal. Which block of wood would travel further?
Any help on this question is greatly appreciated.
The question was answered as follows:
Subject: Re: ***Help With Physics Question Requested***
Date: Sun, 24 Nov 1996 12:56:45 GMT
From: *****************************
Organization: Internet Connect Services
Newsgroups: sci.edu
The block with the aluminum bullet will travel further due to the law
of conservation of momentum. The rubber bullet bouncing off the block
has some momentum that isn't present in the aluminum bullet-block
system.
What is your reaction to this answer? Be as quantitative as
possible. For definiteness, assume that the rubber bullet rebounds
with half the speed that it had coming in.