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Traffic lights are being converted from incandescent bulbs to LED arrays to save operating and maintenance costs. Typically, each incandescent light uses three 100-W bulbs, one for each color R, Y, G. A competing LED array consists of 61 LEDs with each LED requiring 9 V and drawing 20mA of current. There are three arrays per light—R, Y, G. A small city has 1560 traffic signals. Since one light is always on 2417 , how much can a city save in 1 year if the city buys their electricity at

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- = Calculate Avf, Zif, and Zof for the amplifier circuit,Assume he = 50, hie 1.1k2, and identical transistors? 150kQ Vs 5002 HH +25v 10k +6 · 47ΚΩ 47k2 4.7k0} 33 ΚΩ 4.7ΚΩ 10k w 4.7kQ HH Voarrow_forwardFor the four-pole filter in Fig. (2), determine the capacitance values required to produce a critical frequency of 2680 Hz if all the resistors in the RC low-pass circuits are 1.8 K. Also select values for the feedback resistors to get a Butterworth response. Note: For a Butterworth response, the damping factor must be 1.848 for the first stage and 0.765 for the second stage. (2) Re Res ww " = 11arrow_forwardFor the circuit shown in Fig. 2.20, the transistors are identica' and have the following parameters: hje=50, hie = 1.1K, hr =0, and hoe = 0. Calculate Auf, Rif and Rof. Ans: 45.4; 112 KN; 129N. HH 150k 47k R 25 V 10k 47k 4.7k 5μF 33k 4.7k 50µF 50µF 4.7k 4.7k R₁ Roj R1000arrow_forward
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- please solve manually. I need the drawing and the values too. Thank you!arrow_forwardTwo alternators, Y-connected 6.6 kV supply a load of 3000 kW at 0.8 p.f lagging. The synchronous mpedance of first alternator is (0.5+j10) Q/ph and second alternator is (0.4+j12) /ph. First alternator delivers 150 amp at 0.875 lag p.f. The two alterators are shared load equally. Determine the current, p.f., induced e.m.f, load angel, and maximum developed power of each alternator?arrow_forwardA domestic load of 2300 kW at 0.88 p.f lagging and a motors load of 3400 kW at 0.85 p.f lagging are supplied by two alternators operating in parallel. If one alternator is delivering a load of 3300 kW at 0.9 p.f lagging, what will be the output power and p.f of the other alternator?arrow_forward
- Delmar's Standard Textbook Of ElectricityElectrical EngineeringISBN:9781337900348Author:Stephen L. HermanPublisher:Cengage Learning
