Mechanical Engineering

A plane wall with surface temperature 350C is attached with straight rectangular fins( k =235 W/m K). The fins are exposed to an ambient air condition of 25C and the convection heat transfer coefficient is 154 W/m2. Each fin has a length of 50mm, a base of 5 mm thick and a width of 100mm. For a Single fin, using a uniform nodal spacing of 10 mm, determine (a) the finite difference equations, (b) the nodal temperatures by solving the finite difference equations, and (c) the heat transfer rate and compare the result with analytical solution.

A plane wall with surface temperature 350C is attached with straight rectangular fins( k =235 W/m K). The fins are exposed to an ambient air condition of 25C and the convection heat transfer coefficient is 154 W/m2. Each fin has a length of 50mm, a base of 5 mm thick and a width of 100mm. …

A plane wall with surface temperature 350C is attached with straight rectangular fins( k =235 W/m K). The fins are exposed to an ambient air condition of 25C and the convection heat transfer coefficient is 154 W/m2. Each fin has a length of 50mm, a base of 5 mm thick and a width of 100mm. For a Single fin, using a uniform nodal spacing of 10 mm, determine (a) the finite difference equations, (b) the nodal temperatures by solving the finite difference equations, and (c) the heat transfer rate and compare the result with analytical solution. Read More »

Select the lightest column section for column AB in the frame shown. The column is under an ultimate load of 700k and only in-plane behavior is considered. Furthermore, assume that the column immediately above or below AB are the same size as AB. All beams are of W18x40 sections. Fy =50ksi . Assume: Inelastic Behavior. Assume any appropriate assumption

EXPERT ANSWER 1. Here it is given thatUse W14×61Fy = 50ksiNow, design strength of column AB Pu = 2658.45kDesign Strength of column AB = 2658.45k2. Let us first design column AB and then Base plate design must be doneAssuming both ends fixed. The effective length is 0.65×16 10.4 feet.Using LRFD, the factored load is Pu=1.2×350+1.6×450=1,140kips  …

Select the lightest column section for column AB in the frame shown. The column is under an ultimate load of 700k and only in-plane behavior is considered. Furthermore, assume that the column immediately above or below AB are the same size as AB. All beams are of W18x40 sections. Fy =50ksi . Assume: Inelastic Behavior. Assume any appropriate assumption Read More »

Two blocks of mass m1 = 2.00 kg and m2 = 6.00 kg on a frictionless table are connected by a massless string. Forces of magnitude F1 = 10.0N and F2 = 5.00N are applied as shown. The string remains taught during the motion. (a) Draw a free body diagram for each block. (b) Draw a free body diagram for the blocks and string treated as one system. (c) What is the acceleration of the blocks? (d) What is the tension in the string?(e) What are the normal forces exerted by the table on each block? (f) What is the net force (direction and magnitude) acting on m2

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Homework Mathematical Modelling 1. Obtain mathematical models of the mechanical systems shown in Figures (1 and 2). ki 3 wr M *(Output) w ki ka u(1) (Input force) 2 M2 No friction (b) Figure (1) Figure (2) 2. Obtain the transfer function Y(s)/U(s) of the system shown in Figure 3. The input u is a displacement input. m2 WW b . 3. Obtain the transfer function X(s)/U(s) and X,(s)/U(s) of the mechanical system shown in Figure 4. 11 ki kz k2 mi m2 bi b2 Figure (4) 4. Write down the mathematical model and Draw the block diagram then Obtain the transfer function V.(S)/V(s) of the electrical systems shown in Figure (5). Where V (s) denotes the input voltage and Vo(s) denotes the output voltage. C R llll C2 He Figure (5) 5. Consider the liquid-level control system shown in Figure (6). Derive a mathematical model for the following system and find the transfer function between the output flow q2 and input flow q. etq Tank 1 Tank 2 Hith R H2h2 R2 7+92 С 0 +91 C2 Figure (6) 6. Consider the liquid-level control system shown in Figure (7).The controller is of the proportional type. The set point of the controller is fixed. Draw a block diagram of the system, assuming that changes in the variables are small. Obtain the transfer function between the level of the second tank and the disturbance input a Proportional controller 0+41 RI с +90 R2 C2 Figure (7)

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A. Differentiate Coulomb’s and Rankine’s Theories B. Collect the data of at least 5 retaining walls constructed in Pakistan. The details should include the following information. 1. Type and purpose of the wall 2. Technical specification 3. Materials used 4. Current status (Stable/maintained/upgraded) 5. location with photographic evidence 6. your suggestions for improvement or comments on the flaws if exist.

EXPERT ANSWER A.Rankine’s Earth Pressure Theory. The Rankine’s theory assumes that there is no wall friction (δ=0) , the ground and failure surfaces are straight planes, and that the resultant force acts parallel to the backfill slope. Rankine’s Theory At Rest Earth Pressure: The at-rest earth pressure coefficient (Ko) is applicable for determining the active …

A. Differentiate Coulomb’s and Rankine’s Theories B. Collect the data of at least 5 retaining walls constructed in Pakistan. The details should include the following information. 1. Type and purpose of the wall 2. Technical specification 3. Materials used 4. Current status (Stable/maintained/upgraded) 5. location with photographic evidence 6. your suggestions for improvement or comments on the flaws if exist. Read More »

The Hoover Dam, in Arizona, encloses Lake Mead, which contains 10 trillion gallons of water. The dam is 1200 ft wide and the lake is 500 ft deep. ( a ) Estimate the hydrostatic force on the dam, in MN. ( b ) Explain how you might analyze the stress in the dam due to this hydrostatic force.

The Hoover Dam, in Arizona, encloses Lake Mead,which contains 10 trillion gallons of water. The dam is1200 ft wide and the lake is 500 ft deep. ( a ) Estimate thehydrostatic force on the dam, in MN. ( b ) Explain howyou might analyze the stress in the dam due to this hydrostaticforce. EXPERT ANSWER

Dynamics: the slender rod has a mass m and is suspended at its end A by a cord. If the rod receives a horizontal blow giving it an impulse I at its bottom B determine the location y of the point P about which the rod appears to rotate during the impact. Express your answer in terms of some or all variables m, I l and appropriate constants.

Dynamics: the slender rod has a mass m and is suspended at its end A by a cord. If the rod receives a horizontal blow giving it an impulse I at its bottom B determine the location y of the point P about which the rod appears to rotate during the impact. Express your answer …

Dynamics: the slender rod has a mass m and is suspended at its end A by a cord. If the rod receives a horizontal blow giving it an impulse I at its bottom B determine the location y of the point P about which the rod appears to rotate during the impact. Express your answer in terms of some or all variables m, I l and appropriate constants. Read More »

18. Zoom in on the map. Find the pin for Mormon’s Crossing. Which road crosses Oak Creek at this location? 19. Given that Page Springs Cellars offers Rhone-style wines, would Page Springs Cellars have a similar climate to the Rhone River in France? Explain your thoughts. 20. Name three animals that are found in the Lower Verde area.

EXPERT ANSWER 1.Mormons Crossing is a little area along Oak Creek in Cornville, Arizona. Along this creek there are several holes deep enough to swim in, some rapids, and even a rope swing. It’s a great spot to cool off, with plenty of trees shading this riparian beauty. There is a new way for you …

18. Zoom in on the map. Find the pin for Mormon’s Crossing. Which road crosses Oak Creek at this location? 19. Given that Page Springs Cellars offers Rhone-style wines, would Page Springs Cellars have a similar climate to the Rhone River in France? Explain your thoughts. 20. Name three animals that are found in the Lower Verde area. Read More »