Parasitic power theft:

A power line running East-West at 150kVAC carrying a 75 MWatt load is 10 meters overhead. A thief makes a 100 turn loop of insulated copper wire around a plastic garbage can with a 70cm diameter. The voltage generated in this coil is used to charge batteries for a fish-finder, lights and radio in his fish hut. The battery charger is electrically equivalent to a 5 ohm resistor.

a) What orientation of the garbage pail winding will allow the greatest rate of electricity theft?

b) Determine the voltage generated across the battery charger.

c) Residential power costs $0.10/kWh. What is the value of the power stolen per day.

d) Why would metal can be a bad choice?

e) Above the indication is that the other wire for the AC power transmission is very far away. In fact they both hang from the same structure. If each wire carries a 100amp current and they are separated by 50cm, determine the force per unit length on the wires

A 100 g lead ball at a temperature of 100◦C is immersed in 300 g of water with the temperature 20◦C contained in an insulated boiler whose heat capacity can be neglected. What will be the mixing temperature? What entropy change does the ball produce? What entropy change does the water bring?What will be the total entropy change?

A 0.10 kg heavy steel ball with a temperature of 200◦C is thrown into a lake with temperatures 20◦C. Which is the entropy change for the ball, for the sea and for the whole system (universe)

A typical American household uses 26.5 kW-hour of electricity per day, and that electricity is mostly supplied by fossil fuels. If we wanted to instead power a house by solar panels, which receive on average 370 W/m2 from the Sun each day and are 15.7% efficient (fraction of solar energy converted into useable electrical energy), what area of solar panels is needed to power an average American home?

Suppose that a molecular ion with charge -10e is embedded within the 5.0-nm-thick cell membrane of a cell with membrane potential -70 mV.

What is the electric force on the molecule?

Summarizing metaphysics in film. Provide a summary and explain the metaphysical concepts found in the film, the Sixth Sense.

One of the harmonic frequencies of tube A with two open ends is 836 Hz. The next-highest harmonic frequency is 912 Hz. (a) What harmonic frequency is next highest after the harmonic frequency 228 Hz? (b) What is the number of this next-highest harmonic? One of the harmonic frequencies of tube B with only one open end is 2940 Hz. The next-highest harmonic frequency is 3220 Hz. (c) What harmonic frequency is next highest after the harmonic frequency 3780 Hz? (d) What is the number of this next-highest harmonic?

Why can’t the human body sense magnetic fields in our bodies when neurons “fire”

1 For the following questions consider a compound of calcium and chlorine.

a What type of bond do calcium and chlorine form?

b Describe how this bond forms.

c What is the chemical formula for the compound? Explain.

2 For the following questions consider a water molecule, H₂O.

a What type of bond is formed between the oxygen and the hydrogen atoms?

b Describe how these bonds form.

c Explain why there are two hydrogen atoms for each oxygen atom.

3 For the following questions consider a piece of copper wire.

a What type of bond is formed between the copper atoms?

b Describe how these bonds form.

c Explain why copper is a good electrical conductor.

Why do astronomers think there are two basically different types of gamma-ray burst?

A tube at room temperature which is 0.680 m long is open on both ends. Which frequencies of sound will resonate in the tube?

The tube is then covered on one end. Which frequencies of sound will resonate in the tube now?

e) lowest frequency


f) 2nd lowest frequency

g) 3rd lowest frequency

h) What is the highest frequency of audible sound that will resonate in this tube?

1.A 15 pF capacitor is charged to 1 kV and
then removed from the battery and connected
in parallel to an uncharged 65 pF capacitor.
What is the new charge on the second ca-
pacitor?
Answer in units of nC

2.What is the new charge on

3.Find the change in energy.
Answer in units of ?J

You plan to take a trip to the moon. Since you do not have a traditional spaceship with rockets, you will need to leave the earth with enough speed to make it to the moon. Some information that will help during this problem:

mearth = 5.9742 x 1024 kg

rearth = 6.3781 x 106 m

mmoon = 7.36 x 1022 kg

rmoon = 1.7374 x 106 m

dearth to moon = 3.844 x 108 m (center to center)

G = 6.67428 x 10-11 N-m2/kg2

1) On your first attempt you leave the surface of the earth at v = 5534 m/s. How far from the center of the earth will you get?

2) Since that is not far enough, you consult a friend who calculates (correctly) the minimum speed needed as vmin = 11068 m/s. If you leave the surface of the earth at this speed, how fast will you be moving at the surface of the moon? Hint carefully write out an expression for the potential and kinetic energy of the ship on the surface of earth, and on the surface of moon. Be sure to include the gravitational potential energy of the earth even when the ship is at the surface of the moon!

(Please inlude step-by-step solution or even an online video link that can teach me this as well)

A wave in a string has a wave function given by: y (x, t) = (0.0300m) sin [(5.35 m^-1) x + (1.63 s^-1) t]
  where t is expressed in seconds and x in meters. Determine:

a) the amplitude of the wave
b) the frequency of the wave
c) wavelength of the wave
d) the speed of the wave

A 5.00-MΩ Ω resistor and a 5.00-μ μ F capacitor are connected in series with a power supply. 1) What is the time constant for the circuit

Part B A 20.0-μ μ F capacitor has an initial charge of 100.0 μ μ C. 1) If a resistance of 20.0 Ω Ω is connected across it, what is the initial current through the resistor?

Part C A 12.5-μ μ F capacitor is charged to a potential of 30.0 V and then discharged through a 65.0­ Ω Ω resistor. 1) How long after discharge begins does it take for the capacitor to lose 90.0% of its initial charge? (Express your answer to three significant figures.) ms m s 2) How long after discharge begins does it take for the capacitor to lose 90.0% of its initial energy? (Express your answer to three significant figures.) ms m s 3) What is the current through the resistor at the time when the capacitor has lost 90.0% of its initial charge? (Express your answer to three significant figures.) mA m A 4) What is the current through the resistor at the time when the capacitor has lost 90.0% of its initial energy? (Express your answer to three significant figures.) mA

The Doppler effect - the shift in frequency/wavelength of a sound source when there is relative motion between source & observer - and a Sonic Boom - a conical region of compression that forms around the sound source when its speed exceeds the speed of sound in the medium of the source, and results in an observed "boom" when part of the cone passes the observer's location - are two interesting, common, as well as connected phenomena seen this week.

For the Doppler effect, give and discuss briefly two applications, see if you can do one stemming from nature and one technology (man-made).

For the sonic boom, see if you can give two occurrences stemming from nature and two from man-made situations.

Please no handwritten or picture respones - only typed replies.