Challenging Engineering Problems with Detailed Answers

A particular DSL modem operates at 768 kbits/sec. How many bytes can it receive in 1 minute? USB 3.0 can send data at 5 Gbits/sec. How many bytes can it send in 1 minute?
1 Answer
Describe the process of sowing of maize by a seed drill.
1 Answer
a) Describe the operation of a heat pump operating on the theoretical reversed Carnot cycle, with a neat sketch of the layout.b) What modifications are required in order to convert a steam power plant working on the ideal Carnot cycle to a plant operating on the Rankine cycle? Explain briefly why these modifications are necessary to enable the operation of a practical cycle? Illustrate your answer with sketches using appropriate property diagrams (p-v and T-s diagrams).
1 Answer
Cryogenic liquid storage. Liquid oxygen is stored in a thin-walled spherical container, 96 cm in diameter, which is further enclosed in a concentric container 100 cm in diameter. The surfaces facing each other at coated with an emittance of only 0.05. The inner surface is at 95 K, and the outer surface is at 280 K. a. Draw an equivalent electrical circuit. b. What is the heat exchange [W] between the two surfaces?
1 Answer
In pea plants, tall height is dominant over short height. How can two tall plants result in a short offspring.
2 Answers
Calibrations on a recent version of an operating system showed that on the client side, there is a delay of at least 0.5 ms for a packet to get from an application to the network interface and a delay of 1.4 ms for the opposite path (network interface to application buffer). The corresponding minimum delays for the server are 0.20 ms and 0.30 ms, respectively.What would be the accuracy of a run of the Cristian's algorithm between a client and server, both running this version of Linux, if the round trip time measured at the client is 6.6 ms?
1 Answer
A spherical ball of solid, nonporous naphthalene, a "moth ball," is suspended in still air. The naphthalene ball slowly sublimes, releasing the naphthalene into the surrounding air by a diffusion limited process. 1. Estimate the time required to reduce the diameter from 2 cm to 0.5 cm. when the surrounding air is at 347 K and 1.013 x 10^5 Pa. Naphthalene has a molecular weight of 128 g/mole, a solid density of 1.145 g/cm^3, a diffusion coefficient in air of 8.19 x 10^-6 m^2/s, and exerts a vapor pressure of 5 torr (670 Pa) at 347 K.
1 Answer
One of my tools stopped working, and I found that in order to fix it, I need to replace a broken wire. The broken wire has a diameter of 5mm and a length of 15 cm. When it was connected to the battery, a current of 12.5mA flowed through the wire. The only wire that I have at home is the same material, but has a diameter of 2mm. a) If I replace the broken piece of wire with a 15cm length of my 2mm diameter wire, what will happen to the current (increase or decrease)? What is the value of the current through the new wire (assume that its connected to the same battery as the original wire)? Hint: Think about the resistances of the old and new wires. b) How long should the new wire (2mm diameter) be if I want to ensure that the current passing through it is the same as the original wire (12.5mA)?
1 Answer
A small family home in Tucson, Arizona, has a rooftop area of 1967 square feet, and it is possible to capture rain falling on about 56% of the roof. A typical annual rainfall is about 14 inches. If the family wanted to install a tank to capture the rain for an entire year, without using any of it, what would be the required volume of the tank in m3 and in gallons? How much would the water weigh when the tank was full (in N and in lbf)?
1 Answer
It is proposed to absorb acetone from air using water as a solvent. Operation is at 10 atm and is isothermal at 20C. The total flow rate of entering gas is 10 kmol /h. The entering gas is 1.2 mol% acetone. Pure water is used as the solvent. The water flow rate is 15 kmol/h. The desired outlet gas concentration should be 0.1 mol % acetone. For this system, Henry's law holds and Ye = 1.5 X where Ye is the mol fraction of acetone in the vapour in equilibrium with a mol fraction X in the liquid. KGa = 0.4 kmol*m^-3*s^-1 1. Draw a schematic diagram to represent the process. 2. Determine the mole fraction of acetone in the outlet liquid.
1 Answer
Because A-B=A+ (-B), the subtraction of signed numbers can be accomplished by adding the complement. Subtract each of the following pairs of 5-bit binary numbers by adding the complement of the subtrahend to the minuend. Indicate when an overflow occurs. Assume that negative number are represented in 1s complement. Then repeat using 2s complement.a) 01001-11010b) 11010-11001c) 10110-01101d) 11011-00111e) 11100-10101
1 Answer
What factors should be considered in quadcopter motor selection? A) Voltage that matches battery and motor amp-hours B) Amperage and weight C) Maximum revolutions per minute and torque rating D) Power-to-weight ratio and pitch
2 Answers
Which of the following describes boundaries?(1)Boundaries are primarily used to indicate which functions a user will perform as opposed to the functions that a product will perform.(2)Boundaries are primarily used to indicate which functions a product will perform as opposed to the functions that a user will perform.(3)Boundaries are always used to indicate which functions a product will perform and never used for the functions that a user will perform.(4)Boundaries are rarely used to indicate which functions a product will perform and are always used for the functions that a user will perform.
1 Answer
A circuit-switching scenario in whichNcs users, each requiring a bandwidth of 25 Mbps, must share a link of capacity 150 Mbps.A packet-switching scenario withNps users sharing a 150 Mbps link, where each user again requires 25 Mbps when transmitting, but only needs to transmit 10 percent of the time.What is the probability that a given (specific) user is transmitting, and the remaining users are not transmitting?
1 Answer
A peasant finds himself on a riverbank with a wolf, a goat, and a head of cabbage. He needs to transport all three to the other side of the river in his boat. However, the boat has room for only the peasant himself and one other item (either the wolf, the goat, or the cabbage). In his absence, the wolf would eat the goat, and the goat would eat the cabbage. a) Solve this problem for the peasant or prove it has no solution. (Note: The peasant is a vegetarian but does not like cabbage and hence can eat neither the goat nor the cabbage to help him solve the problem. And it goes without saying that the wolf is a protected species.)
1 Answer
Steam at a pressure of 0.08 bar and a quality of 93.2% enters a shell-and-tube heat exchanger where it condenses on the outside of tubes through which cooling water flows, exiting as saturated liquid at 0.08 bar. The mass flow rate of the condensing steam is 3.43 x 10^5 kg/h. Cooling water enters the tubes at 15.8C and exits at 35.8C with negligible change in pressure.1. Neglecting stray heat transfer and ignoring kinetic and potential energy effects, determine the mass flow rate of the cooling water, in kg/h, for steady-state operation.
1 Answer
Steam enters an adiabatic condenser (heat exchanger) at a mass flow rate of 5.55 kg/s where it condensed to saturated liquid water at P = 20 kPa. The change in enthalpy of the steam is 2,491 kJ/kg. The steam is cooled by water from a river. Environmental regulations require that the maximum increase in the river water temperature is 10C. a) What is the minimum mass flow rate of river water through the condenser to cool the steam? The Cp for water = 4.184 kJ/kg/K.
1 Answer
Find the requested quantities for the circuit. We used the mesh-current method to identify the meshes. We then identified the mesh currents and wrote a KVL equation for each mesh and a constraint equation for the dependent source that defines its controlling variable in terms of the mesh currents. We solved these equations simultaneously for the unknown mesh currents and constrained current, and we checked the solution by verifying that the power in the circuit balances Now use the mesh-current values to calculate the voltage v0 and the total power generated in the circuit. Enter your answers directly on the figure.
1 Answer
Helium is used as the working fluid in a Brayton cycle with regeneration. The pressure ratio of the cycle is 8, the compressor inlet temperature is 300 K, and the turbine inlet temperature is 1800 K. The effectiveness of the regenerator is 75 percent. Determine the thermal efficiency and the required mass flow rate of helium for a net power output of 60 MW, assuming both the compressor and the turbine have an isentropic efficiency of (a) 100 percent and (b) 80 percent. The properties of Helium are cp = 5.1926 kJ/kg.K and k = 1.667.
2 Answers
It is required to design and implement: 1. A counter which counts from 0 to 255 with seven segment display. 2. A logic function y=( 0,3,5,10,16,20,30 35). 3. Summing and subtracting circuit of 8 digit numbers. 4. ROM (a,b,c,d) to 60 to 75 in binary. 5. A timing module which counts time in us or ms or seconds.
1 Answer
Wheels A and B have weights of 150 lb and 100 lb , respectively. Initially, wheel A rotates clockwise with a constant angular velocity of 100 / A rad s and wheel B is at rest. If A is brought into contact with B, determine the time required for both wheels to attain the same angular velocity. The coefficient of kinetic friction between the two wheels is 0.3 k and the radii of gyration of A and B about their respective centers of mass are 1 A k ft and 0.75 B k ft . Neglect the weight of link AC.
1 Answer
Design a rectangular metallic waveguide to be used for transmission of electromagnetic power at 2.45 GHz. This frequency should be at the middle of the operating frequency band. The design should also allow maximum power transfer without sacrificing the operating bandwidth. In each case, you should use a safety factor of 10 and neglect ohmic loss in the conductors.a. Design an air-filled guide to meet the given specifications. Find the maximum power the waveguide can transmit. The breakdown electric field in air is assumed to be 2 x10^6 V/m b. Now assume that a electric material is used to fill the waveguide. The material is characterized by = 2.5 o, = o and = 0. The breakdown field in the dielectric is 10^7 V/m. How many times more power can be transmitted by this waveguide?
1 Answer
Need help fast I been stuck in this for the longest
1 Answer
In addition to bandages and gauze, it's recommended that a first aid kit also contain
1 Answer