Mechanical Engineering Answers

The car travels at a constant speed from the bottom A of the dip to the top B of the hump.if the radius of curvature of the road at A is PA=120 m and the car acceleration at A is 0.4g, determine the car speed v.if the acceleration at B must be limited to 0.25g, determine the minimum radius of curvature pB of the road at B.

1-     A p projectile is launched with an initial seed of 200 m/s at an angle of 60 with respect to the horizontal> compute the range R as measured up the incline

A simply supported beam ABCD is subjected to a uniform distributed load along AB

and CD as shown in Figure Q2. The properties of the beam are: E = 70 GPa and INA = 3010

6 mm4

. Determine the deflection of the beam at point B. Next, change the pin support at point A to a fixed support. Develop the slope and

deflection functions.

The end a And B of arod of length l are maintained temperature 0 degree celcius and 100 degree celcius until steady state condition. Suddenly temperature at the end Ais increased to 20 degree celcius and B decreased to 60 degree celcius find the temperature distance in th rod at time t

DESIGN OF A SPEED REDUCER WITH SPUR GEARS

Consider that you are the designer of a speed reducer that is part of of the power transmission for a tractor. The Tractor’s engine operates at a fairly high speed, while the drive for the wheels must rotate more slowly and transmit a higher torque that is available at the output of the engine.

The design process will start first by listing the functions of the speed reducer or the functional requirements of the reducer. Some probable functions can be stated as follows:

Functions:

1.         To receive power from the engine of the tractor through a rotating shaft.

2.         To transmit the power through machine elements that reduce the speed to a desired value.

3.         To deliver the power at a lower speed to an output shaft that ultimately drives the wheels of the tractor.

Secondly the design requirements shall be stated. As a member of the design team for the tractor, you would be able to identify such requirements from your own experience and ingenuity and or by consultation with fellow designers, marketing staff, manufacturing engineers, service personnel, suppliers, and customers.

The product realization process calls for personnel from all of these functions to be involved from the earliest stages of design.

Design Requirements:

1.    The reducer must transmit H_in [kW] power. (Note that power assignment is listed for each student separately in kW!)

2.    The input is from a six-cylinder diesel engine with a rotational speed, n_in = 2000 rpm.

3.    The output shaft of the reducer delivers the power at rotational speed n_out = of 290 ± 1 rpm. (Output speed is the same for all students!)

4.    A mechanical efficiency of greater than 95 % is desirable.

5.    The minimum output torque capacity of the reducer should be _______ N-m. (This output torque will depend on your input power and the specified output speed.)

6.    The reducer output shaft is connected to the drive shaft for the wheels of the farm tractor. Therefore, a moderate shock (at output) will be encountered.

7.    The input and output shafts must be inline.

8.    The reducer (gear) housing is to be fastened to a rigid steel frame of the tractor.

9.     Small size is desirable. (e.g., your gearbox size will depend on the transmitted power assigned to you) must be given as Width x Length times heigth)- - given such as, 510 x 510 mm with a maximum height of 610 mm. (These will differ for your case!)

10. The tractor is expected to operate 8 hours per day, 5 days per week, with a design life of 15 years.

11. The reducer must be protected from the wheather and must be capable of operating anywhere at temperatures ranging from -5 b ⁰ C to 55 ⁰ C.

12. Flexible couplings will be used on the input and output shafts to prohibit axial and bending loads from being transmitted to the reducer.

13. The production quantity is 1 000 units per year!

14. Moderate cost is critical to successful marketing.

15. All government and industry safety standards must be met (this shall add a bonus for every positive answer.).

Problem 1 : 5 kg of air experience the three processes cycle as shown in figure. Calculate the network take R= 0.287 ⁄ .

Problem 1 : 5 kg of air experience the three processes cycle as shown in figure. Calculate the network take R= 0.287 KJ/K.g.k

what is meant by jump phenomenon in cam follower mechanism

how compressive strength and the bending strength of gear tooth are considered for the design of speed reducer

Q12. Show that for the flow in the stokes law region, the terminal falling velocity of a spherical particle in a fluid medium may be given by vt = [4𝐷(𝜌𝑠−𝜌)𝑔3𝐶𝐷𝜌]1/2