PHYS 132, WEEK #3
21.2. Model: The principle of superposition comes into play whenever the waves overlap. Visualize:
The snapshot graph at t = 1 s differs from the graph t = 0 s in that the left wave has moved to the right by 1 m and the right wave
PHYS 132, WEEK 11 November 29-December 3
19.3. Solve: (a) During each cycle, the heat transferred into the engine is Q H = 55 kJ , and the heat exhausted is Q C = 40 kJ . The thermal
efficiency of the heat engine is
h = 1QC QH = 140 kJ 55 kJ = 0.273
15.1. Solve: The density of the liquid is
m 0.120 kg 0.120 kg = = = 1200 kg m 3 V 100 mL 100 10 -3 10 -3 m 3
Assess: The liquid's density is more than that of water (1000 kg/m3) and is a reasonable number.
15.2. Solve: The volume of the helium
10:1 ANatural Money" Called Energy
1. One month, John has income of $3000, expenses of $2500, and he sells $300 of stocks.
a. Can you determine Johns liquid assets L at the end of the month? If so, what is L? If not,
Why or? I40 , VJL 60"0idt'l'
Andy Gawne Phys-0133-51 Problem 32.45 Problem: a) What is the magnetic field strength 2 m from a long, straight wire carrying a current of 10 A? b) What percentage of the earth's magnetic field is your answer to (a)? c) High-voltage transmission line
Andy Gawne PHYS 133-51
Problem: The capacitors are charged and the switch closes at t = 0s. At what time has the current in the 8 resistor decayed to half the value it had immediately after the switch was closed? Model: We assume that the wire is i
Our first experience with magnetic field is with
magnet bars. Our observation shows that two magnet
bar could repel or attract each other depending to
their relative orientation.
Each magnet has two poles north pole our south pole.
As Oersted experiment showed, electric current can produce
magnetic field. Faraday an English physicist aware of
Oerested experiment, did an experiment to see if magnetic
field can produce electric current. His experiment proved
Electric Current and Direct-Current Circuit
Flow of electric charge in a conductor is called
electric current. Consider the following conductor,
is amount of the electric charge that passes through
the cross-section area
Then electric current is
Capacitors and Dielectrics.
The simplest way to store electric energy is to separate
negative and positive charges from each other. The
simplest instrument that can be used to do this, is consist
of two parallel rectangular plates of area A that are
Sources of Magnetic Field:
In 1820 Christian Oersted observed that electric current
in circuit causes the deflection in the nearby compass.
He realized that electric current can produce magnetic
field. As we can see in the following Figure magnets line
When several electrical elements like resistors,
capacitors, batteries, and are connected to each
other by conducting wires, then we say that we have
an electrical circuit.
In order to find current and voltage for each element
Electric potential Energy and Electric potential.
In gravitational field we know the work done by
gravity to move an object a distance upward is
The same way, we can say that when a positive
charge moved a distance against the direction of
Suppose that some fluid passing through cylinder
with length and cross-sectional area .
The amount of fluid that passes this cross section per
unit time is equal to
Here is called mass flux density and mass flux
through surface is
In physics 131we learned that there are four
fundamental forces in nature,
1. Strong nuclear force.
2. Electromagnetic force.
3. Weak nuclear force.
4. Gravitational force.
We will discuss electromagnetism during this quarter.
Andy Gawne PHYS-0133-51 Problem 29.48 Problem: A proton is fired with a speed of 200,000 m/s from the midpoint of the capacitor toward the positive plate. Show that this is insufficient speed to reach the positive plate. What is the proton's speed as
Andy Gawne PHYS-0133-51 Problem 26.45 Problem: A thin rod with length L has a charge of Q. Find an expression for the electric field E at a distance x from the end of the rod. Give your answer in component form. Model:
Visualize: The figure shows th
Solve: Figure (i) shows a weightlifter (WL) holding a heavy barbell (BB) across his shoulders. He is standing on a rough surface (S) that is a part of the earth (E). We distinguish between the surface (S), which exerts a contact forc
7.1. Solve: (a) From t = 0 s to t = 1 s the particle rotates clockwise from the angular position +4 rad to -2 rad. Therefore, = -2 - ( +4 ) = -6 rad in one sec, or = -6 rad s . From t = 1 s to t = 2 s, = 0 rad/s. From t = 2 s to t = 4 s the partic
19.1. Model: The heat engine follows a closed cycle, starting and ending in the original state. The cycle
consists of three individual processes. Visualize: Please refer to Figure Ex19.1. Solve: (a) The work done by the heat engine per cycle is the a