Other Engineering Answers

A 4 m long steel wire having 40 mm in diameter, a Young`s modulus of 20 × 〖10〗^10 N/m^2 and an elastic limit of 2.5 × 〖10〗^8 N/m^2 is used to support a weight of 100 KN .
a) By how much does the wire stretch under this load ?
b) what is the maximum weight the steel wire is able to support without being permanently deformed?

You are working as a software developer in a company named Blue Moons Inc. Your team has been assigned the task of developing software that would assist the users to store and retrieve personal information. According to the requirement specifications, the software should provide the functionality to store contact details of various people. It should also enable the user to store the details of meetings and appointments. In addition, the software should display reminders to alert the user for meetings and appointments.

As the software is required to assist the user for storing and retrieving personal information, it has been named as Personal Assistant.



Design Specifications

The Personal Assistant software should be designed to meet the following specifications:

n When the application is executed, a menu with the following options should be displayed:

l Contact details

l Meetings/appointments

On selecting either of the preceding options, a submenu with the following options should be displayed:

l Add new record

l Delete record

l Edit record

l Search record

The Contact details option would enable the user to add, edit, delete, and search the contact details of various people. The contact details include information, such as name, address, phone number, and email address.

Similarly, the Meetings/appointments option enables the user to add, edit, delete, and search meeting/appointment details. The meeting/appointment details include information such as date of meeting/appointment, time, location, and duration of meeting.

Critical note on Pakistan environmental protection act?

A piledriver hammer of mass 150 kg falls freely through a distance of 5 m to strike a pile of mass 400 kg and drives it 75 mm into the ground. The hammer does not rebound when driving the pile. Determine the average resistance of the ground.

A vehicle of mass 700 kg accelerates uniformly from rest to a velocity of 60 kmh−1 in 10 s whilst ascending a 15% gradient. The frictional resistance to motion is 0.5 kN. Making use of D’Alembert’s principle, determine:
i) the tractive effort between the wheels and the road surface
ii) the work done in ascending the slope
iii) the average power developed by the engine

A rear wheel drive car of mass 1300kg has a rolling resistance of 150 N, a frontal area of 1.6m2, a drag coefficient of 0.30, a transmission loss of 17% and a maximum engine power of 50kW. Assuming that the traction limit for each tyre is equal to the weight that it carries (i.e. the tyre traction coefficient =1) and that 60% of the vehicle weight is on the rear wheels during acceleration,

a) What is the maximum power available at the back wheels?
b) What is its theoretical maximum speed in mph on a level road?
c) What is its theoretical maximum speed in mph up a 1 in 7 hill?
d) What is the maximum tractive force that each of the rear tyres could provide under acceleration before slipping occurs? (NB this is per rear wheel not per axle!!)
e) What would be the maximum, useable, tractive force at each of the rear tyres if full power was applied at 30 mph? (hint: is this limited by tyre grip or by engine power?)
f) What would be the wind resistance at 30 mph?
g) What would be the acceleration (in mph/s) at 30