A manufacturing operation requires 50 fc on the workplane in a 100 ft x 150 ft facility. The walls and ceilings are painted white. The work plane is 25 feet below the lights.
1. Calculate how many high-bay 400-W metal halide fixtures are required
2. Calculate how many 6-lamp T8 HBF fixtures are required.
In: Mechanical Engineering
. A steam main (outside diameter of 16.8 cm and inside diameter of 15.4 cm) is covered with 5-cm of high temperature insulation (k = 0.095 W/m. K) and 3.8 cm of lower temperature insulation (k = 0.07W/m. K). Calculate the heat loss from 150 m pipe assuming that inner and outer surface temperatures of the insulation are 450 and 30 °C, respectively. Also determine the temperature at the interface between two layers of insulation (10 points).
In: Mechanical Engineering
For H2O, determine the specified property at the
indicated state.
(a) T = 140°C, v = 0.5 m3/kg. Find
p, in bar.
(b) p = 30 MPa, T = 120°C. Find v, in
m3/kg.
(c) p = 10 MPa, T = 450°C. Find v, in
m3/kg.
(d) T = 80°C, x = 0.8. Find p, in bar,
and v, in m3/kg.
In: Mechanical Engineering
The surface energy of a single crystal depends on crystallographic orientation. Does this surface energy increase or decrease with an increase in planar density? Why? (Hint: Read “External Surface” part in S.4.6: Surface energy is proportional to the number of unsatisfied bonds of surface atoms)
please clear hand writing, also plesae don't give me the book answer.
Thank you.
In: Mechanical Engineering
Find one example of a product where the largest or most detrimental environmental impact persumably derived from each of the following:
1. Raw Material Acquisition
2. Production
3. Consumption
4. Disposal
In: Mechanical Engineering
One integrated circuit design calls for the diffusion of arsenic into silicon wafers; the background concentration of As in Si is 2.5 × 1020 atoms/m3. The predeposition heat treatment is to be conducted at 1000°C for 45 minutes, with a constant surface concentration of 8 × 1026 As atoms/m3. At a drive-in temperature of 1100°C, determine the diffusion time required for a junction depth of 1.2 μm. For this system, values of Qd and D0 are 4.10 eV and 2.29 × 10−3 m2/s, respectively. (The answer is NOT 49.12hours)
In: Mechanical Engineering
Leaf springs are commonly used in low-cost or high-stiffness vehicle suspensions, e.g. golf cars, light-truck rear axle. Consider a cold-drawn AISI 1040 flat leaf spring subjected to a fluctuating loading condition of maximum and minimum stresses of 420 MPa and 140 MPa respectively for a total of 50,000 cycles. The loading condition of the spring then changes to maximum and minimum stresses of 350 MPa and -200 MPa respectively. Estimate the remaining life of the spring under the new loading condition using Palmgren-Miner cumulative damage theory. Assume that the fully-corrected endurance limit is 200 MPa and Sn is 90% of Sut.
In: Mechanical Engineering
As mechanical engineering explain the reason why an early airbag was a failure, and the reason any system acquisition processes that were not followed that may have contributed to the failure.
In: Mechanical Engineering
(H) Angle conversions. 2.47 deg = A rad. 3.72 rad=B deg. 3.67 rad=C rev. 3.0300 rad = D deg E min F sec. Round F to the nearest second. There are 6 answers.
In: Mechanical Engineering
1. Using the equations describing the standard atmosphere, plot
the speed of sound (in m/s, ft/s and knots) in the altitude range
sea level – 32 km. You can use Matlab or Excel (10 points).
2. An airfoil has a critical Mach number of ??? = 0.65. The wing is
swept back at 30°. a) What is the design flight Mach number for
this wing? (2 points)
b) What is the design flight speed in knots at an altitude of
30,000 ft? (10 points)
3. A supersonic passenger plane is traveling at an altitude of
60,000 ft. A normal shock forms in front of the nose of the plane.
A pitot-static system on the nose (behind the shock) measures the
pressure ratio between stagnation pressure and static pressure to
be 1.2256. a) Calculate the flight Mach number of the aircraft (12
points).
c) Calculate the required wing sweep for minimum wave drag. (4
points)
3. A fighter jet passes over you at Mach 1.6 at an altitude of h =
10000 m. What is its horizontal distance x from you when you hear
the sonic boom? (6 points)
In: Mechanical Engineering
Design an electro-pneumatic circuit to control a double-acting
cylinder via a 5/2 way singlesolenoid valve. The on switch is of
detent type and when actuated, the piston will repeatedly extend
and retract until the switch is released. The length of forward
stroke and the speed of forward and return motion should be
adjustable via roller-limit switches and flow control valves
respectively.
(a) Show pneumatic and electrical circuits for indirect control of
the system described above, i.e. each switch in the circuit
indirectly controls the output components via a dedicated relay.
[15]
(c) Redesign your circuit incorporating non-contact sensing for
piston position detection using three-wire capacitive sensors.
In: Mechanical Engineering
Part 2: MATLAB
Exercise 1 (50 pts)
Write a program that tells the user if a city of their choice is in a tropical, temperate, or polar region. Use the cities.txt file provided in the Files section of this class. Your program should read the data in that file, find the city given by the user, and return a text message with the information. If the city is not found, your program should write a message accordingly. To decide which region each city falls into, use the table below.
Latitude | Region |
Above 66 N | Polar |
Between 35 N and 66 N | Temperate |
Between 35 S and 35 N | Tropical |
Between 35 S and 66 S | Temperate |
Below 66 S | Polar |
HINT: If you follow the file reading methods explained in our video tutorial, your data will be in cell format. There are a few functions that could be very useful in this case: strcmp compares two strings (one of which can be in a cell) to see if they match. Also, cell2mat converts a cell array into an ordinary array. Finally, find finds indices and values of any non-zero elements in an array.
See the output examples below:
What city are you interested in? Caracas Caracas is in a tropical region What city are you interested in? Merced City not found!
https://catcourses.ucmerced.edu/files/1587454/download?download_frd=1
In: Mechanical Engineering
1.What is the purpose of the diffuser section of a gas turbine engine, and under what principle does it operate?
2.Why do some axial flow gas turbine engines use multiple compressors?
3.What happens in a compressor stall?
4.Why is a variable exhaust nozzle required in an engine equipped with an afterburner?
In: Mechanical Engineering
Q) Explain in brief, the importance of Energy Auditing and Energy Management. With the use of a case study, explain its significance at your workplace?
In: Mechanical Engineering
Air undergoes a polytropic process in a piston–cylinder assembly from p1 = 1 bar, T1 = 295 K to p2 = 7 bar. The air is modeled as an ideal gas and kinetic and potential energy effects are negligible. For a polytropic exponent of 1.4, determine the work and heat transfer, each in kJ per kg of air, (1) assuming constant cv evaluated at 300 K. (2) assuming variable specific heats.
In: Mechanical Engineering