Point A needs to send a 50 kb file to point B. Each packet will contain L = 1000 bits of data. The distance between Points A and B is d = 50 km. The propagation velocity is V = 2 x 108 m/sec. The transmit data rate is N = 10 Mbps. Sliding Window flow control is used with a window size (W) of five. Both points A and B have buffers large enough to handle the sliding window protocol.

How long would it take to transfer the file from point A to point B?

a. Time to transmit one frame:
b. Time to transmit W frames:c. Time to propagate last bit of the first frame from A to B:
d. Time to propagate ACK frame from B to A:
e. Total time to transmit and acknowledge first frame:
f. Time to transfer file:

Asteel wire of 2 mm diameter is fixed between two points located 2 m apart. the tensile force in the wire is 250n, if its density of steel is given by 7830 kg/m3 the fundamental frequency of vibration hz? ?

Acommercial grade cubical freezer, 4 m on a side, has a composite wall consisting of an exterior sheet of 5.0-mm thick plain carbon steel (kst= 60.5 w/m k), an intermediate layer of 100-mm thick polyurethane insulation (kins 0.02 w/m k), and an inner sheet of 5.0- mm thick aluminium alloy (kal polyurethane insulation and both metallic sheets are each characterized by a thermal contact resistance of r 2.5 x 104 m2 k/w. (a) what is the steady-state cooling load that must be maintained by the refrigerator under conditions for which the outer and inner surface temperatures are 25°c and -5°c, respectively? (b) for power saving purpose, which wall material should be increased/reduced in. thickness in order to reduce 50% of the cooling load found in part (a)? redesign the thickness of the proposed material. 177 w/m-k). adhesive interfaces between the q=575.93 w

In the winter, in order to keep the classroom steadily at 68 f before 10 pm, heating with an average rate of 42,000 btu/hr is provided. assume the outdoor temperature maintains at 32°f, determine the electrical power (kw) required to (a) operate a reversible heat pump (b) operate a real heat pump with a cop (7) of 4.5 and (c) operate an electrical-resistance heater.