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 »

What are some of the reasons why plastic shaping processes are important?

EXPERT ANSWER The reasons include (1) many of the processes are net shape processes. (2) in general, less energy is employed than in metalworking processes. (3) lower temperatures are required to process plastics than metals or ceramics . (4) there is great flexibility in geometry and (5) painting and other finishing processes are generally not …

What are some of the reasons why plastic shaping processes are important? Read More »

Annealed low-carbon steel has a flow curve with strength coefficient = 75,000 lb/in2 and strain-hardening exponent = 0.25. A tensile test specimen with gage length = 2.0 in is stretched to a length = 3.3 in. Determine the flow stress and average flow stress that the metal experienced during this deformation.

Annealed low-carbon steel has a flow curve with strength coefficient = 75,000 lb/in2 and strain-hardening exponent = 0.25. A tensile test specimen with gage length = 2.0 in is stretched to a length = 3.3 in. Determine the flow stress and average flow stress that the metal experienced during this deformation. Flow stress = Enter …

Annealed low-carbon steel has a flow curve with strength coefficient = 75,000 lb/in2 and strain-hardening exponent = 0.25. A tensile test specimen with gage length = 2.0 in is stretched to a length = 3.3 in. Determine the flow stress and average flow stress that the metal experienced during this deformation. Read More »