Question 11

9. (10%) If a homeowner with an R 4.0 house paid $350/month for his natural gas bill and the house next door had an R 14.0 house of the same area, what would you expect for the natural gas bill for the R 14.0 house?

10. (10%) If two houses had the same R and AT values, but the second house had twice the area,what would the monthly natural gas bill be for the second house if it were $200 for the first house?

Task 1 Your company is currently working on a project - Solar Tracker. Solar tracker is an automated tracker which uses LDR to sense the sunlight. A microcontroller reads the LDR voltage and signals the connected motor which rotates the panel towards the Sun.

23. Figure below shows the surface wind velocity as a function of the natural log ofthe roughness length (Z). Plot a straight line and determine the roughness length(Zo) of the terrain if measurement points are: V1 = 2.5 m/s and V2 = 3.6 m/s.Steps: Plot V1 and V2 and determine LN(Z1) and LN(Z2) and use equation 15from lecture notes to get Zo. (5%)

For the basic parameters for Wind Turbine Classes, CC1 refers to: (1%) a) Load bearing structural components that when failed would result in major failure of wind turbine. b) Load bearing structural components that when failed would not result in major failure of wind turbine. c) Mechanical components that attached to the main structure.

8. (10%) Heat flow is given by the equation Q/t = A x AT/R, where the heat flow per time is Q/t, the thermal resistance is R, the area is A. The difference in temperature on the two sides of the wall is AT in degrees Celsius. If A and AT are constant, and the R value is improved from 4.0 to 14.0, what is the relative heat flow as a percentage in the R 14.0 wall compared with the R 4.0 wall?

2. (10%) A ball of mass 2.00 kg is dropped from a height of 15.0 m. What is the greatest velocity it will have just before hitting the ground if one ignores air resistance?

Incorrect Question 1 You had a conversation with friends about PV technology, before taking the lesson. Some people used the term PV modules and other used PV panel. Which of the following is correct? A "Module" is a combination of PV cells They are the building block for PV array "Modules" are also known as PV "Panel" and they can be used interchangeably 0/1 pts O All of the above

Question 11 The bypass diode is installed on PV module so that: Current always flows through it to prevent cell damage Current flows through it once a day when voltage across the modules equals Zero Cells can be shaded without any damage so this diode is almost never used 0/1 pts Provides alternative path for current to flow when cells are shaded to prevent cell damage when module is shaded

9. (10%) A small transformer used for a doorbell steps down the voltage from 120 V at 0.10 A,(wattage 1) to 12 V, (wattage 2). What is the current flow to the doorbell, (wattage 2), assuming the transformer is 100% efficient? Recall IinEin=IoutEout.