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1. Consider a three-phase power system with one-line diagram shown in Figure 1. The three-phase trans- former between CBs 1 and 2 (CB: circuit breaker) nameplate ratings are listed: 5MVA, 13.8A-138.0YkV, the transformer reactance X₁1 = 3.80 (viewed from low voltage side 13.8kV, resistance is negligible). The impedance of the transmission line between CBs 3 and 4 is ZL1 = (10+j100). -(50 pts) (a) Pick up SB = 100MVA for the entire three-phase system, and rated voltage VB = 138.0kV, calculate the per-unit line L1 and transformer impedance values. (b) If an SLG fault occurs at the midpoint of the line (L2) between CBs 5 and 6, which breaker(s) should operate? If the CB 5 or CB 6 does not operate, which breaker(s) will provide the backup protection? (c) List the operating CB(s) for different zones, which are listed in Figure 2. (d) If the second generator is connected at bus 3, the system (generators, buses, and transmission lines) is protected by overcurrent relays R1 to R12. Assuming the directional overcurrent relays are used for three transmission lines, what is the remote backup relay(s) for R7? And why? G Generator mm www Transformer - GSU Bus 1 depending on which breakfas Bus 3 Transmission line L1 Shunt Reactor L3 Shunt Capacitor Figure 1: A three-phase power system. Bus 2 Distribution Transformer Feeder

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Assuming a 1-KB page size, what are the page numbers and offsets for the following address references (provided as decimal numbers): а. 3085 b. 42095 c. 215201 d. 650000

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The beaver, Canada’s national animal, have some unusual characteristics. One unusual fact about beavers is their large size. The beaver is the largest rodent in North America, weighing from 13 to 35 kg. It spend a lot of time in the water,so its feet is large and webbed for swimming. The beaver's tail which is wide and flat like a paddle also helps it to swim. Thick underfur keep the beaver warm and dry, even in very cold water. In fact, beavers have been known to stay under water in icy ponds for as long as fifteen minutes. Beavers also has long teeth which grows all their lives. They use these powerful teeth to cut down trees which they use for food and shelter. Another unusual fact about the beaver is that it is one of the few animals that change its own environment. Beavers create ponds by building dams with roots, sticks, mud and stones. Each family of beavers build a lodge,or nest, in a riverbank or in the middle of a pond. They build an underwater entrance to the lodge. Having the entrance underwater protects them from their enemies. Beavers is also very social animals. They not only communicate with each other by making sounds with their mouths but also by slapping their big flat tails on the water. The beaver's social life is complex and focus around the female. These very special animals are found in every province in Canada.

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4. (P10, Page72)Consider a packet of length L that begins at end system A and travels over three links to a destination end system.These three links are connected by two packet switches. Let d;, si, and R¡ denote the length, propagation speed, and the transmission rate of link i, for i=1,2,3. The packet switch delays each packet by d proc- Assuming no queuing delays, in terms of d;, si, Ri, (i=1,2,3), and L, what is the total end-to-end delay for the packet? Suppose now the packet is 1,500 bytes, the propagation speed on all three links is 2.5*10$m/s, the transmission rates of all three links are 2 Mbps, the packet switch processing delay is 3 m sec, the length of the first link is 5,000 km, the length of the second link is 4,000 km, and the length of the last link is 1,000 km. For these values, what is the end-to-end delay?

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Q1. Calculate capillary rise/fall in a glass tube 2 mm diameter when immersed in (a) water (b) mercury.Both the liquids are at 20°C and the surface tension values at this temperature for water and mercury are 0.072 N/m and 0.052 N/m respectively. The specific gravity of mercury is 13.6. The contact angle of water and mercury are 0° and 130° respectively.

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4.57 Two boxes, A and B, are connected to each end of a light vertical rope, as shown in Fig. P4.57. A constant upward force F =80.0 N is applied to box A. Starting from rest,box B descends 12.0 m in 4.00 s. The tension in the rope connecting the two boxes is 36.0 N.|(a) What is the mass of box B? (b) What is the mass of box A?

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A thin 30-cm x 30-cm flat plate is pulled at 3 m/s horizontally through a 3.6-mm-thick oil layer sandwiched between two plates, one stationary and the other moving at a constant velocity of 0.3m/s, as shown in Fig. P2-77. The dynamic viscosity of the oil is 0.027 Pa-s. Assuming the velocity in each oil layer to vary linearly, (a) plot the velocity profile and find the location where the oil velocity is zero and (b) determine the force that needs to be applied on the plate to maintain this motion.

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4-29 A piston-cylinder device contains 0.85 kg of refrigerant-134a at -10°C. The piston that is free to move has a mass of12 kg and a diameter of 25 cm. The local atmospheric pres-sure is 88 kPa. Now, heat is transferred to refrigerant-134auntil the temperature is 15°C. Determine (a) the final pres-sure, (b) the change in the volume of the cylinder, and (c) the change in the enthalpy of the refrigerant-134a.

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The switch in the circuit has been closed for a long time, and it is opened at t=0. Find v(t) for t>= 0. Calculate the initial energy stored in the capacitor. (a). When the switch is closed, calculate the value of Vc. (b). When the switch is opened, find the time constant. (c). Find v(t) for t>= 0. (d). Find p(t) for t>= 0. (e). Calculate the initial energy stored in the capacitor.

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5.34 • Consider system shown in Fig. E5.34. Block A weighs 45.0 N and block B weighs 25.0 N. Once block B is set into downward motion, it descends at a constant the E speed. (a) Calculate the coefficient of kinetic friction between block A and the tabletop. (b) A cat, also of weight 45.0 N, falls asleep on top of block A. If block B is now set into downward motion, what is its acceleration (magnitude and direction)?

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