HW 12 Solutions
From Hot to Cool: The Second Law of Thermodynamics
a) What happens to the entropy of a bucket of water as it is cooled down (but not frozen)?
Q < 0
It stays the same.
b) What happens to the entropy of a
HW 1 Solutions
Equilibrium of a Mobile Conceptual Question (Conceptual Question). The artist Anya
Calderona constructs the mobile shown in the figure. In the illustrated configuration, the mobile
is perfectly balanced.
If Anya decides to make the star twi
HW 9 Solutions
Understanding Heat Conduction
Conduction-the flow of heat from a hotter object to a cooler object or from a hotter region to a
cooler region of the same object-is the most common mechanism of heat transfer. The formula
governing this is
HW 7 Solutions
What Is a Sound Wave?
a) Based on the information presented in the introduction of this problem, what is a sound wave?
Propagation of pressure fluctuations in a medium
b) Having established that a sound wave
corresponds to pressure fluctuat
HW 6 Solutions
a) Traveling waves propagate with a fixed speed usually denoted as v (but sometimes c). The
velocity v is the phase velocity. The waves are called periodic if their waveform repeats every
time interval T.
The fundamental relat
HW 8 Solutions
Normal Modes and Resonance Frequencies
a) The string described in the problem introduction is oscillating in one of its normal modes.
Which of the following statements about the wave in the string is correct?
The wave is traveling in the +x
HW 11 Solutions
Isobaric, Isochoric, Isothermal, and Adiabatic Processes
Consider a system consisting of an ideal gas confined within a container, one wall of which is a
movable piston. Energy can be added to the gas in the form of heat by applying a flam
HW 10 Solutions
Introduction to the Ideal Gas Law
a) A gas sample enclosed in a rigid metal container at room temperature (200C) has an absolute
pressure p1. The container is immersed in hot water until it warms to 400C. What is the new
HW 5 Solutions
Energy of Harmonic Oscillators
As you know, a common example of a
harmonic oscillator is a mass attached to a
spring. In this problem, we will consider a
horizontally moving block attached to a
spring. Note that, since the gravitational
HW 4 Solutions
The escape velocity is defined to be the minimum speed with which an object of mass m must
move to escape from the gravitational attraction of a much larger body, such as a planet of total
mass M. The escape velocity is a fu
HW 7 Solutions
Buoyant Ping-Pong Ball
A Ping-Pong ball is held submerged in a bucket of water by a string attached to the bucket's
a) Salt is now added to the water in the bucket, increasing the density of the liquid. What
happens to the tension i
HW 2 Solutions
Test Your Understanding 11.1: Conditions for Equilibrium
A drum major marching in a parade tosses his baton in the air. As the baton rises and falls, it
rotates at a uniform rate. Which condition(s) for equilibrium does this motion satisfy?
Section 2.4, Problem 27
We are asked to show whether the transformation
x + x2
for which the solution is not unique
is invertible. As we saw in section, there are y =
and there are y for which no solution exists