1. The primary of a step-up transformer connected to a 120 V source has 200 turns. If the output is 480 V, how many turns does the secondary have?
2. The primary of a step-down transformer connected to a 240 V source has 1500 turns. The secondary has 200 turns. What is the output voltage of this transformer?
3. A laptop computer requires 24 volts to operate properly. A transformer with 600 turns in the primary needs to have how many turns in the secondary to operate the computer from a 120 V source?
4. If the output current for the transformer in the previous problem is 4.5 A, calculate the input current.
5. A transformer has an input of 24 V and an output of 36 V. If the input is changed to 12 V what will the output be?
6. A model electric train requires 12 V to operate. When connected to a household voltage of 120 V, a transformer is needed. If the primary coil has 250 turns, how many turns must the secondary coil have?
7. A transformer has 25 turns in the primary coil and 200 turns in the secondary coil. If 24 V is connected to the primary coil and a 20-Ω device is connected to the secondary coil, calculate the current in Amperes passing through the device.
8. Neon signs need 12,000 V to operate. If a transformer operates off a 240 V source and has 1000 turns in its primary coil, how may turns must the secondary coil have?
9. A power of 200 kW is delivered by power lines with 48,000 V difference between them. Calculate the current, in amps, in these lines.
10. If the lines in problem #9 above, have a resistance of 100-Ω, calculate the change of voltage along each line.
In: Physics
A) If two events A and B are __________, then P(A and B)=P(A)P(B).
complements
independent
simple events
mutually exclusive
B)
The sum of the probabilities of a discrete probability distribution must be _______.
less than or equal to zero
equal to one
between zero and one
greater than one
C) Which of the below is not a requirement for binomial experiment?
The probability of success is fixed for each trial of the experiment.
The trials are mutually exclusive.
For each trial there are two mutually exclusive outcomes.
The experiment is performed a fixed number of times.
D) If p is the probability of success of a binomial experiment, what is the probability of failure?
−p
x/n
n/x
1-p
In: Statistics and Probability
An experiment on rice variety IRS at six seeding rates was conducted in an RCBD with four replications. The results of the experiment are shown below:
Treatment, Kg
Grain Yield, Kg/ha
Seed/ha
R1
R2
R3
R4
25
5113
5398
5307
4678
50
5346
5952
4719
4264
75
5272
5713
5483
4749
100
5164
4831
4986
4410
125
4804
4848
4432
4748
150
5254
4542
4919
4098
Construct an ANOVA table for the Experiment.
Interpret the results of the ANOVA.
Estimate the Coefficient of Variation and state the importance of
it.
Write the model of the experiment.
In: Statistics and Probability
4.11 Consider the hardness testing experiment described in Section 4.1. Suppose that the experiment was conducted as described and that the following Rockwell C‐scale data (coded by subtracting 40 units) obtained:
| Coupon | |||||
| Tip | 1 | 2 | 3 | 4 | |
| 1 | 9.3 | 9.4 | 9.6 | 10.0 | |
| 2 | 9.4 | 9.3 | 9.8 | 9.9 | |
| 3 | 9.2 | 9.4 | 9.5 | 9.7 | |
| 4 | 9.7 | 9.6 | 10.0 | 10.2 | |
In: Statistics and Probability
| Excel Assignment (Percentage-of-completion) | |||
| Required: | |||
| 1- Using the data provided below you are to input formulas in the area designated below to calculate: % complete, revenue to be recognized in each year, and gross profit to be recognized in each year. (10 points) | |||
| Hint: I suggest you use formulas with an IF function regarding the gross profit section of your speadsheet because your spreadsheet should be able to calculate correct answers whether a contract generates a profit or loss. | |||
| 2- Using the data given and the solutions your spreadsheet generated, prepare all journal entries for 2017. Whevenver possible, the amounts for your journal entries should be formulas that reference the appropriate cells in the calcuations below. (10 points) | |||
| 3-Once you have completed the spreadsheet save your file with your last name(s) and first name(s) and upload it under Assignments by the assignment due date. | |||
| Data: | |||
| Contract price | 1,200,000 | ||
| 2016 | 2017 | 2018 | |
| Costs incurred to date** | $280,000 | $600,000 | $785,000 |
| Estimated costs yet to be incurred | 520,000 | 200,000 | 0 |
| Customer billings to date** | 250,000 | 500,000 | 1,200,000 |
| Collections of billings to date** | 120,000 | 320,000 | 1,040,000 |
| **Hint: You have to figure out the actual cost, billings, and collections for each respective year. The information presented is "to date" not "Costs expended this year" as in the handouts and some of your assigned exercises/problems. | |||
| Use the format provided below to input formulas for each respective year. | |||
| 2016 | 2017 | 2018 | |
| Costs expended to date | |||
| Estimated total costs | |||
| % complete | |||
| Contract price | |||
| % complete | |||
| Revenue recognized to date | |||
| Revenue recognized prior | |||
| Revenue recognized current | |||
| Estimated total gross profit | |||
| % complete | |||
| Gross profit recognized to date | |||
| Gross profit recognized prior | |||
| Gross profit recognized current | |||
In: Accounting
A sinusoidal voltage is given by v(t)=7 cos(172t+28o) V. What is the first time in ms for t>0 for which v(t) has a zero crossing?
In: Electrical Engineering
Let V and W be finite dimensional vector spaces over a field F with dimF(V ) = dimF(W ) and let T : V → W be a linear map. Prove there exists an ordered basis A for V and an ordered basis B for W such that [T ]AB is a diagonal matrix where every entry along the diagonal is either a 0 or a 1.
In: Math
Prove
1. For each u ∈ R n there is a v ∈ R n such that u + v= 0
2. For all u, v ∈ R n and a ∈ R, a(u + v) = au + av
3. For all u ∈ R n and a, b ∈ R, (a + b)u = au + bu
4. For all u ∈ R n , 1u=u
In: Advanced Math
Assume that random variable x^2 has a chi-squared distribution with v degree of freedom. Find the value of “A” for the following cases
1) P(X^2 <=A) =.95 when v = 6
2) P(X^2>=A) =.01 when v = 21
3) P(A <= X^2 <= 23.21)= .015 when v = 10.
In: Math
As shown in the figure below, a bullet is fired at and passes through a piece of target paper suspended by a massless string. The bullet has a mass m, a speed v before the collision with the target, and a speed (0.496)v after passing through the target. The collision is inelastic and during the collision, the amount of kinetic energy lost by the bullet and paper is equal to [(0.263)Kb BC] , that is, 0.263 of the kinetic energy of the bullet before the collision. Determine the mass M of the target and the speed V of the target the instant after the collision in terms of the mass m of the bullet and speed v of the bullet before the collision. (Express your answers to at least 3 decimals.)
V = ? v
M = ? m
In: Physics