1. A 3-phase, 5 kVA, 208 V, 4-pole, 60 Hz, star-connected synchronous generator has negligible stator winding resistance and a synchronous reactance of 8 Ω per phase at the rated terminal voltage. The generator is connected in parallel to a 3-phase, 208 V, 60 Hz infinite bus. All losses may be neglected.

a)   Determine the excitation voltage and the power angle when the machine is delivering rated apparent power at 0.8 PF lagging.

b)   If the field excitation is increased by 20 % without changing the prime mover power, find the stator current, power factor, and reactive power supplied by the machine.

c)   With the field current as in (a), determine the maximum power with which the generator can be supplied without losing synchronism? What are the corresponding stator current and power factor at this maximum power condition?

Part 1) Linda just sold all the shares of company A stock that she owned for $156/share. She purchased the stock one year ago for $150/share. Over the year, she received $1/share in dividend. Calculate the return on her investment.

Part 2) The interest rate on one-year Treasury-bond is 0.4%, the rate on two-year Treasury bond is 0.8%, the rate on three-year T-bond is 1.1%.

a. Compute the expected interest rate in the second year (year 2)

b. Compute the expected interest rate in the third year (year 3).

Part 3) The expected inflation rate for the next three years are estimated: 2.5% for 2020, 3.5% for 2021, and 4.2% for 2022. Calculate the inflation premiums (IP) for 1-year bond, for 2-year bond and 3- year bond.

A cola-dispensing machine is set to dispense 10 ounces of cola per cup, with a standard deviation of 0.8 ounce. The manufacturer of the machine would like to set the control limit in such a way that, for samples of 31, 5% of the sample means will be greater than the upper control limit, and 5% of the sample means will be less than the lower control limit.

1. At what value should the control limit be set? (Round z values to two decimal places. Round your answers to 2 decimal places.)

2. If the population mean shifts to 9.7, what is the probability that the change will not be detected? (Round your intermediate calculations to 2 decimal places and final answer to 4 decimal places.)

3. If the population mean shifts to 10.4, what is the probability that the change will not be detected? (Round your intermediate calculations to 2 decimal places and final answer to 4 decimal places.)

You are a CFO considering the impact that you could have on your firm if you could lower your WACC. You would like to lower your WACC by 20% of its current level. You currently have 30% debt in your capital structure with a before-tax cost of 8.5% and a beta of 0.25, and an equity cost of 15.64%. The risk-free rate is 5% and your current equity beta is 0.76. Your firm has invested in three projects, with 30% in project 1 (beta of 1.1), 30% in project 2 (beta of 0.8), and 40% in project 3 (beta of 0.2175). The tax rate is 40%. If you increase the debt in your capital structure to 90%, will you have met your goal of lowering your WACC? Show all of your work (support your answer).

You are a CFO considering the impact that you could have on your firm if you could lower your WACC. You would like to lower your WACC by 20% of its current level. You currently have 30% debt in your capital structure with a before-tax cost of 8.5% and a beta of 0.25, and an equity cost of 15.64%. The risk-free rate is 5% and your current equity beta is 0.76. Your firm has invested in three projects, with 30% in project 1 (beta of 1.1), 30% in project 2 (beta of 0.8), and 40% in project 3 (beta of 0.2175). The tax rate is 40%. If you increase the debt in your capital structure to 90%, will you have met your goal of lowering your WACC? Show all of your work (support your answer).

We aim a red (620 nm) laser onto a small screen that has two slits that are 0.1 mm apart. Each slit has a width of 0.03 mm.The light coming out of the two slits is projected onto a big screen a distance X from the slits. In the photo on the right you can see the pattern that’s visible on the big screen.Using a ruler, we determine that the distance between two adjacent bright spots is equal to 12 mm.The red laser has a wavelength of 620 nm and its beam has a circular cross section with a diameter of 0.8 mm. The power rating of the laser “1.5 mW“ (i.e. 1.5 milliwatts) which we may assume is the power of the light coming out of the laser.

1. [4 points] Calculate how many photons are being emitted by the laser each second.

In an air conditioning system, the inside and outside conditions of air are 25 °C DBT and 50%
RH, and 40 °C DBT and 27 °C WBT, respectively. The room sensible heat ratio is 0.8, while
50% of the room air is rejected to atmosphere and replaced with an equal quantity of fresh air
before entering the air conditioning apparatus. If the fresh air added is 100 m3
/min and the air
density is 1.2 kg/ m3 with zero air by-passing, determine: a) Room sensible and latent load, b)
Sensible and latent heat due to the fresh air, c) Apparatus due point, d) Humidity ratio and dry
bulb temperature of the air entering to the air conditioning apparatus. Ans. a) 53.96 kW,
14.04 kW; b) 30.67 kW, 39.73 kW; c) 11.8 °C; d) 0.0138 kg/ kg dry air, 32.5 °C

Why is crowding out an important issue in the debate over the merits of discretionary fiscal policy? Is crowding out equally likely to occur during all phases of the business cycle?

Keynesian economists emphasize the effects of fiscal policy on aggregate demand whereas supply-side economists focus on the effects on aggregate supply. Discuss the process by which a tax reduction might result in an increase in real output and employment according to these two approaches. If tax reductions are beneficial for the economy, why doesn't the government slash taxes to zero.

Assume that the economy's marginal propensity to consume is 0.8. To combat a recession, suppose that the federal government increases its expenditures by $50 billion. If prices remain constant, what impact will this policy have on the economy's aggregate demand and real output? Instead, suppose that prices increase as the economy's aggregate demand increases. What effect would this have on your answer?

A manufacturer of computers claims its newest model has a mean battery life of 10 hours, although normally distributed variations in computer production will cause some units to have more or less battery life. A consumer advocacy group is concerned the true mean is less and is constructing a hypothesis test at the 95% significance level to evaluate the claim. In their testing for battery life, a sample of 25 randomly selected units gave a sample mean of ̄x25 = 9.6, with sample standard deviations25= 0.8. (a) Clearly state the null hypothesis and alternate hypothesis for the test. (b) Determine the appropriate test statistic and compute it. (c) On the basis of this test statistic value, what conclusion does the test reach regarding the battery life claims? (d) If the conclusion reached happens to be incorrect, would it be a type I error or type II error? Explain.

2)

A three-phase synchronous generator is rated 16 kV and 200 MVA, has negligible losses and has reactance of 1.65 pu. The generator is operated on an infinite bus of 15 kV voltage and delivers 100 MVA at 0.8 Power Factor, lagging.

a)Determine the internal voltage (E_i), the power angle (δ), and the line current of the machine.

b)If the field current of the machine is reduced by 10%, while the mechanical power input to the machine is maintained constant, determine the new value of the power angle (δ) and reactive power delivered to the system.

c)The prime mover is next adjusted without changing the excitation so that the machine delivers zero reactive power to the system. Determine the new power angle (δ) and the real power being delivered to the system.

d)What is the maximum reactive power that the machine can deliver if the level of excitation is maintained as in part b?