How the concentration polarization occurs in galvanic and electrolylic cells (in details)

mechanism of each cell

Two charges are placed along the x axis such that charge A is at -3 m, and has a charge of 2.5e-06 C. Charge B is at 2.2 m, and has a charge of -2.5e-06 C.
What is the x component of the force (in Newtons) felt by charge A due to charge B?
What is the x component of the force (in Newtons) felt by charge B due to charge A?
Suppose a third charge were to be placed at position C, -5.6 m on the x axis. What is the x component of the electric field at position C?

How much horsepower would a car need to tow a boat up the Davis Dam Grade Climb?

Pro Tips

Davis Dam assumed grade = 7%

Air density is sea level conditions (.002377 slugs/f^t3)

w(weight) of the boat + trailer + car = 3,922,000 + 150,000 + 4451 Lbs

Crr = coefficient of rolling resistance = .015

Assume Combined CDA is 1555 ft^2

SAE J2807 (Davis Dam Grande Climb) - min speed is 40mpg (59 ft/s)

F(drag) = 1/2p x V^2 x C(d)A

F(rolling resistance) = W x cos x Crr

F(weight) = W x sin

F(sum) = F(drag) + F(rr) + F(weight)

P = F(sum)XV

convert to horsepower = P(1hp/550ft lbf/sec)

Concentrated solar power is a method of using the Sun's light to produce useful energy on Earth. A large system of mirrors collects light during the day and focuses it on a target which is raised to a high temperature. The energy delivered to the target is then used to generate steam which runs turbines to produce electricity. The mirrors do not have to be circular, and for some designs they focus light along a line rather than to a point .

Concentrated solar power is a practical alternative to direct solar "photovoltaic" electric because the efficiency is high and because the energy collected may be stored, for example in molten salts. However, it has a very significant environmental impact on wildlife because intense converging light may endanger birds and bats. A way to reduce that risk is to lower the temperature by collecting light in long cylindrical troughs.

1. Suppose you wanted to collect power sufficient for 10,000 homes, which on average use about 10,000 kilowatt hours a year each. Given a solar constant of 1.4 kW/m², at a site with 300 clear days a year, how much area would be needed to gather the power required? Assume the turbines have an efficiency of 40% and there are 8 hours a day of useful sunlight. Given that area, if it is covered by mirrors in a square array, what is the size of the square along one side in meters? Explain.

2. To save birds and avoid singed technicians, you design the array to use cylindrically shaped mirrors focusing light to a line on long pipes. In this way the delivered power is distributed over a larger target and the temperature of the target is kept low. What is the ideal shape of the mirror? If approximately that shape were a cylinder with a diameter of 4 meters, where would the pipe have to be above the mirror's surface?  

3. The source of the energy collected by this power station is the fusion of hydrogen within the Sun's core where it is converted to helium with a small loss of mass. How much mass does the Sun lose each year to deliver this energy to a solar power system on Earth?

The average net torque Justin exerts on a discus about its axis of spin is 100 Nm during a throw. The mass of the discus is 2 kg, and its radius of gyration about the spin axis is 12 cm. If the discus is not spinning at the start of Justins throwing action, and the throwing action lasts for 0.20 s, how fast is the discus spinning when Justin releases it?

Wrap up question 1: You hold a “Top” piece of charged tape near an uncharged soda can. Describe the behavior of the tape. Would the behavior be different if you used a “Bottom” piece of tape instead? Explain.

Wrap up question 2: Suppose there exists a third type of charge in addition to the two types we associate with glass and plastic. Call this third type X charge. What experiment(s) could you use to test whether an object has X charge? State clearly how the outcome(s) of the experiment(s) would be interpreted.

Wrap up question 3: A positively charged electroscope has separated leaves. Describe what will happen if you bring a negatively charged rod near, but not touching, the top of the electroscope.

A 7.25-kg bowling ball moving at 8.65 m/s collides with a 0.75-kg bowling pin, which is scattered at an angle of θ = 85.5° from the initial direction of the bowling ball, with a speed of 14 m/s. calculate the direction, in degrees of the final velocity of the bowling ball. B) Calculate the magnitude of the final velocity in meters per second of the bowling ball.

Place 4 charges at the corners of a square which is 2 meters by 2 meters (4 large squares along each length). Place two +1 nC charges at adjacent corners and two -1 nC charges at the other two corners.

Determine the direction of the electric field at the following three points:
Point E halfway between two like charges. (-120 degrees, 50 V/m)
Point F halfway between two opposite charges. (-90.5 degrees, 309 V/m)
Point G at the center of the square. (90 degrees, 210 V/m)

1. For the points E, F and G, draw a diagram showing both charges and the two individual field vectors (one for each charge) and explain why their vector sum points in the direction that you.

2. Determine the electric potential at the points E, F and G. List them numerically and give an explanation for their value  

If the mass of the charge is very small (mass = 2.9×10^-25kg) so that its weight (weight in Newtons = mass in kg × 9.8 m/s2) is negligible compared to the electric force, what is the magnitude of its acceleration? Recall Newton's 2nd Law.

the magnitude of the electric force is 27.68×10^−17?

Write your result in terms of 10^9 m/s2. For example, if the result is 1.234 ×10^9 m/s2, just enter 1.234 (keep 3 decimal places).

You stand 17.5 m from a wall holding a tennis ball. You throw the tennis ball at the wall at an angle of 38.5 ∘ from the ground with an initial speed of 21.5 m / s. At what height above its initial position does the tennis ball hit the wall? Ignore any effects of air resistance.  

4/ You are operating a fan with the characteristics shown in the figure below. The 25 kW fan currently operates continuously at full speed with the flow reduced to 90% of its rated capacity using downstream dampers. An evaluation reveals that there is inadequate fresh air being introduced into the building during the day, and too much is supplied at night. The flow rate needs to increase to 100% from 7am to 7pm, and can be reduced to 50% at night. What would be the CHANGE in energy costn per year if this change was done using either downstream dampers, or using a 97% efficient VSD ?

• ηmot = 0.96 at the nominal speed

• ηmot = 0.94 at 90% of the nominal speed

• ηmot = 0.89 at 50% of the nominal speed

• Electricity costs $0.15/kWh, no impact on demand charges

A diverging lens (f = -20cm) is placed 10cm to the left of a plane mirror. A match stick is placed 25cm to the left of the lens. (I) Where is the final image of the stick? (II) Is the image real or virtual? Upright or inverted? (III) What is the magnification? (IV) Where is the final image relative to the mirror?

A 0.046-nm x-ray is incident on a stationary electron. A scattered photon is observed at 94°.

Find the energy of the scattered photon E'_γ= ______ keV and its wavelength λ'= _________ nm

Find the kinetic energy of recoiled electron

K= _______keV

Find the speed of recoiled electron as a fraction of speed of light: v/c= ________