Mechanical Engineering Answers

A high-rise tower built by a developer contains 200 condominium units. The QA department of the developer has to approve the tower before turning it over to sales. The QA department will select a random sample of 8 units and inspect them. If more than three major defects are found in any unit, they will reject the unit as defective. If more than 2 of the 8 inspected units are defective, the entire tower will be rejected. If 10 of the 200 units are known to have more than three major defects, what is the probability that the tower will be rejected?

A multi plate clutch has three plates and four pressure plates, pressed together by an axial force of 500N. µ = 0.3. The outer radius of the plates is 100mm, and the inner radius is 80mm. Calculate the torque that the clutch can transmit. If the inner radius and axial force are to remain the same, but the torque is increased by 25%, what must the outer radius than be? (use uniform wear theory)  

Precalculus

Good day sir could you please assist for solutions to this problems for Precalculus Pre-engineering, which is due today.

*Problem 1*

For the expression

f(x)=log((1-|x|) ÷ (1+|x|))

Determine:

• it's largest domain;

• it's intersections with the x-axis (if any);

• it's intersection with the y-axis (if any);

• it's sign;

• when appropriate, end behaviours and behaviours at accumulation points of the domain which are not in the domain, possible symptoms.

*Problem 2*

Compute, showing the procedure,

limit from x to positive infinity ( square root symbol with x^2 - 3x - square root symbol with x^2 - 5x + 1)

*Problem 3*

Compute, showing the procedure.,

limit from x to negative infinity of the expression (square root with x^6 - x^2)÷(1-2x)

*Problem1*

f(x) = log((1-|x|)÷(1+|x|))

•It's largest domain

•It's intersections with the x-axis (if any)

•It's intersection with the y-axis (if any)

•It's sign

•when appropriate, end behaviours and behaviours at accumulation points of the domain which are not in the domain, possible asymptotes.

*Problem 2*

Compute, showing the procedure,

limit from x to positive infinity of the problem encircled in brackets ( square root symbol x^2-3x - square root symbolx^2-5x+1)

*Problem 3*

Compute, showing the procedure,

limit from x to negative infinity of the expresion: (square root symbol x^6-x^2)÷(1-2x)

A manufacturing company produces bearings. One line of bearings is specified to be 1.64 centimeters (cm) in diameter. A major customer requires that the variance of the bearings be no more than 0.001 cm2. The producer is required to test the bearings before they are shipped, and so the diameters of 16 bearings are measured with a precise instrument, resulting in the following values: 1.69 1.62 1.63 1.70 1.66 1.63 1.65 1.71 1.64 1.69 1.57 1.64 1.59 1.66 1.63 1.65 Assume bearing diameters are normally distributed. Use the data and α = 0.025 to test the data to determine whether the population of these bearings is to be rejected because of too high variance.

A horizontal axis wind turbine has a rotor diameter of 76 m and reaches its full load output at the generator terminals of 2 MW at a wind speed of 12 m/s. The overall efficiency of the gearbox and generator is 94 %. Assume the density of air is 1.2 kg/m3 and calculate the power coefficient (Cp) of the aerodynamic rotor [6]

Question 1 [20]

A simple gear train of 30 and 50 teeth for pinion and gear wheel respectively, is used to drive an electric wheelchair at a velocity that is double the maximum velocity of slip. The pinion has an equal addendum as the gear wheel, a module of 3 mm, and a pressure angle of 14.5o. The wheelchair has a maximum velocity of 5 m/s when its pinion rotates at 800 r.p.m. Calculate:

1.1. The

1.2. The

1.3. The

1.4. The

1.5. The

1.6. The

magnitude of the velocity of slip of gears in mesh. (2) angular speed of the gear wheel in rad/s. (4) maximum length of a path of the approach in mm. (2) length of a path of a recess in mm. (7) addendum of the gears in mm. (7) contact ratio. (8)

Question 1 [20]

A simple gear train of 30 and 50 teeth for pinion and gear wheel respectively, is used to drive an electric wheelchair at a velocity that is double the maximum velocity of slip. The pinion has an equal addendum as the gear wheel, a module of 3 mm, and a pressure angle of 14.5o. The wheelchair has a maximum velocity of 5 m/s when its pinion rotates at 800 r.p.m. Calculate:

1.1. The

1.2. The

1.3. The

1.4. The

1.5. The

1.6. The

Question 2

magnitude of the velocity of slip of gears in mesh. (2) angular speed of the gear wheel in rad/s. (4) maximum length of a path of the approach in mm. (2) length of a path of a recess in mm. (7) addendum of the gears in mm. (7) contact ratio. (8)

 In a jib crane, the jib and tie rod are 5 m and 4 m long respectively. The height of crane post is 3 m and tie rod remains horizontal. Determine the forces produced in the jib and tie rod when a load of 2 kN is suspended at the crane head