1(25) Short Answer Questions
a(5) Using m, l and t as the symbols for the dimension of mass, length and
time, what are the dimensions of force and momentum ?
The units of force are Newtons, or kg m/s2 . For momentum, we have mass
times velocity, or kg m/s
1(50) A Vibrating Molecule
k
A diatomic molecule can be treated as two
identical masses, m, attached by a a spring
of constant k as shown in the upper part
of the Figure. It can be shown that this is
equivalent to a single mass m attached to a
spring on c
Matter & Interactions I: 33131
Fall 2011
Practice Exam 3, 1 December, 2011
1(35) Inelastic and Elastic Collisions Two balls of identical size and speed, v , have a
head-on collision as shown in the gure below. The ball to the left has a mass m and
the bal
1(50) Quantum Systems
A quantum object is known to have ve energy levels. In order to learn about the
system, you shine light on a cold collection of many of these objects. In measuring the
light coming through the system, you observe that the following w
1(35) Two masses, m1 and m2 undergo a collision. As seen in the lab frame, m1 is
initially moving with velocity v1 = v1 x and m2 is at rest. This is shown in the
picture below. We will consider the system of the two masses both before, and
after the colli
1(50) Exponential Potential
Two interacting objects have a potential energy as a function of the separation between
them given by the expression
U (r) = rer ,
where r is the separation between the two objects and and are positive constants
of the appropri
Matter & Interactions I: 33131
Fall 2012
Practice Exam, 25 October, 2012
Name (print) SOLUTION KEY
Last,
First
Section:
Name (sign)
This exam is 6 pages long. If you are missing a page, please contact the invigilator (proctor).
There are 100 points possib
1(50) Mr Conehat is developing a stunt for the circus using a spring-like device that he has
developed. He calls it a sproing, and notes that like a spring, the stored potential energy
depends on the compression or stretch of the sproing. If he denes the
Matter & Interactions I: 33131
Fall 2010
Exam, 22 October, 2010
Name (print) Solution Key
Last,
First
Section:
Name (sign)
This exam is 8 pages long. If you are missing a page, please contact the invigilator
(proctor). There are 100 points possible in thi
1(50) The Grand Prix
Mr. Conehat has entered the Pittsburgh Vintage Grand Prix in Schenley park. As part of his tryout
for the race, he needs to drive his speedster (car) around a circular track of radius R at a constant
speed v as shown in the left-hand
1(20) Short Answer Questions
a(5) Two objects interact with each other via a force along the line which connects them. If the force
obeys reciprocity. What do we know about the forces that the two masses exert on each other?
If the force is recipricol, th
1(50) The Gas Cloud
A small satellite of mass m has been placed in a circular orbit around the center
of a large, spherical, uniform density, c , gas cloud of radius R. The satellites
orbit, with radius r, is actually inside of the cloud, but the clouds d
1(40) Gravitational Systems
Two heavy spherical (radius 0.05R) objects are located at xed positions along
2M
m
2M
0
R
an axis in space. The rst mass is centered at r = 0 and has a mass of 2M .
The second mass is centered at r = R and has a mass of 2M . A