Mechanical Engineering Answers

As shown in figure, find

that at what distance body A

will attain a velocity of 3 m/s

when starts from rest.

Assume coefficient of

friction as 0.2 for block and

surface and pulleys are

frictionless and weightles

Two spur gears in mesh have a module 2.5 mm, center-to-center distance of 50 mm, and a magnitude of speed ratio of 0.6. How many teeth do the gears have?

The moment generating function of a probability distribution is given by

Mx(t) = (1 − t/μ)−1, μ > t.

Find the moment generating function of Y = 3x − 5.

A screw jack is to lift a load of 80 kN through a height of 400 mm. The elastic strength of screw material in tension and compression is 200 MPa and in shear 120 MPa. The material for nut is phosphor-bronze for which the elastic limit may be taken as 100 MPa in tension, 90 MPa in compression and 80 MPa in shear. The bearing pressure between the nut and the screw is not to exceed 18 N/mm2 . Consider factor of safety equal to 2 and coefficient of friction between screw and nut (µ)= 0.14. Design the screw and nut only. Refer the table shown as below for standard dimensions of screw.

A vertical channel 152 × 76 has a cantilever beam bolted to it as shown. The channel is hot-rolled AISI 1006 steel. The bar is of hot-rolled AISI 1015 steel. The shoulder bolts are M10 × 1.5 ISO 5.8. For a design factor of 2.0, find the safe force F that can be applied to the cantilever.

A vertical channel 152 × 76 has a cantilever beam bolted to it as shown. The channel is hot-rolled AISI 1006 steel. The bar is of hot-rolled AISI 1015 steel. The shoulder bolts are M10 × 1.5 ISO 5.8. For a design factor of 2.0, find the safe force F that can be applied to the cantilever. 

A uniform beam, 1.5 metre long, is suspended in a horizontal position by two vertical support rods as shown in the figure below. Rod A has a diameter of 12 mm and manufactured from steel with E_steel = 210 GPa. Rod B has a diameter of 16 mm and is made from copper with E_copper = 105 GPa. This simply supported beam is to carry a motor vehicle engine and gearbox weighing 5,5 kN.

1 2 3 4 5 5.1 Determine the distance ‘x’ from the left-hand support ‘A’ in order for the beam to remain in a horizontal position.                                                                                                   /7/

5.2 Calculate the stress in each rod due to the applied load.                                                 /4/

5.3 Calculate the movement (extension) of the support wires under this 5.5 kN load.        /2/

Will the rods be able to withstand the applied load? Motivate your answer.

 A cone of base diameter 40 mm and height 50 mm is resting centrally on the top of square frustum whose smaller base is 40 mm, larger base is 50 mm and height 60 mm. The square base frustum is resting on its smaller base. Draw an isometric view of the solids.

1500kg of steam is to be produced per hour with an enthalpy of 3077kj/kg. The feed water supplied to the boiler has an enthalpy of 167.5 kj/kg. The velocities of the water at inlet and the steam at exist are 2m/s and 45m/s respectively. Find the rate of which heat must be supplied to the boiler.

a fluid enters a turbine at the rate of 14kj/s with an initial enthalpy of 2762kj/s and leaves with a final enthalpy of 2607kj/kg. Find the power developed if the turbine has an efficiency of 0.85.