Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
8th Edition
ISBN: 9781305387102
Author: Kreith, Frank; Manglik, Raj M.
Publisher: Cengage Learning
Bartleby Related Questions Icon

Related questions

Question
100%
I need solutions to this questions Don't use Artificial intelligence
4:58 PM P
Prince Mech
Just now
+17846
:
«
300 LEVEL
UNIVERSITY OF ABUJA
FACULTY OF ENGINEERING
DEPARTMENT OF MECHANICAL ENGINEERING
2023/2024 SESSION
FIRST SEMESTER EXAMINATIONS
Course Code/Title: MEE 311-THEORY OF MACHINES
INSTRUCTIONS: (i). Attempt FIVE (5) questions.
QUESTION 1 (20 marks)
Time: 3 hours.
(ii) All questions carry equal marks
a) What are the differences between Mechanisms and Machines?
6mks
b) With respect to mechanisms and machines, define the following terms: (i) Rigid body (ii) Lower pairs
(iii) Inversions (iv) Link
6mks
c) Identify the type of body and degree of freedom (DOF) in the systems/structures shown below: Smks
(a)
☐
QUESTION 2 (20 marks)
(b)
a) State the types of chains available in mechanisms.
(c)
(d)
8mks
b) Mention and sketch the inversion used for the mechanism in I.C. engines, steam engines and
reciprocating compressor mechanism.
c) Fig. 2.1 shows the layout of a quick return
mechanism of the oscillating link type, for a
special purpose machine. The driving crank BC
is 30 mm long and time ratio of the working
stroke is to be 1.7. If the length of the working
stroke of R is 120 mm, determine the dimensions
of AC and AP.
7mks
Smks
QUESTION 3 (20 marks)
ay For a Screw Jack, state the mathematical expressions to determine the following parameters:
(i) Helix Angle (ii) Torque to lift load
(iii) Maximum Efficiency
6mks
8mks
b) An electric motor driven power screw moves a nut in a horizontal plane against a force of 75 kN at a
speed of 300mm/min. The screw has a single square thread of 6 mm pitch on a major diameter of 40
mm. The coefficient of friction at the screw threads is 0.1. Estimate power of the motor.
c) The pitch of 50 mm mean diameter threaded screw of a screw jack is 12.5 mm. The coefficient of
friction between the screw and the nut is 0.13. Determine the torque required on the screw to raise a
load of 25 kN, assuming the load to rotate with the screw. determine the ratio of the torque required to
raise the load to the torque required to lower the load and also the efficiency of the machine. 7mks
MEE 311, 2023/2024
=
о
כ
Մ
Reply
expand button
Transcribed Image Text:4:58 PM P Prince Mech Just now +17846 : « 300 LEVEL UNIVERSITY OF ABUJA FACULTY OF ENGINEERING DEPARTMENT OF MECHANICAL ENGINEERING 2023/2024 SESSION FIRST SEMESTER EXAMINATIONS Course Code/Title: MEE 311-THEORY OF MACHINES INSTRUCTIONS: (i). Attempt FIVE (5) questions. QUESTION 1 (20 marks) Time: 3 hours. (ii) All questions carry equal marks a) What are the differences between Mechanisms and Machines? 6mks b) With respect to mechanisms and machines, define the following terms: (i) Rigid body (ii) Lower pairs (iii) Inversions (iv) Link 6mks c) Identify the type of body and degree of freedom (DOF) in the systems/structures shown below: Smks (a) ☐ QUESTION 2 (20 marks) (b) a) State the types of chains available in mechanisms. (c) (d) 8mks b) Mention and sketch the inversion used for the mechanism in I.C. engines, steam engines and reciprocating compressor mechanism. c) Fig. 2.1 shows the layout of a quick return mechanism of the oscillating link type, for a special purpose machine. The driving crank BC is 30 mm long and time ratio of the working stroke is to be 1.7. If the length of the working stroke of R is 120 mm, determine the dimensions of AC and AP. 7mks Smks QUESTION 3 (20 marks) ay For a Screw Jack, state the mathematical expressions to determine the following parameters: (i) Helix Angle (ii) Torque to lift load (iii) Maximum Efficiency 6mks 8mks b) An electric motor driven power screw moves a nut in a horizontal plane against a force of 75 kN at a speed of 300mm/min. The screw has a single square thread of 6 mm pitch on a major diameter of 40 mm. The coefficient of friction at the screw threads is 0.1. Estimate power of the motor. c) The pitch of 50 mm mean diameter threaded screw of a screw jack is 12.5 mm. The coefficient of friction between the screw and the nut is 0.13. Determine the torque required on the screw to raise a load of 25 kN, assuming the load to rotate with the screw. determine the ratio of the torque required to raise the load to the torque required to lower the load and also the efficiency of the machine. 7mks MEE 311, 2023/2024 = о כ Մ Reply
Expert Solution
Check Mark
Knowledge Booster
Background pattern image
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Principles of Heat Transfer (Activate Learning wi...
Mechanical Engineering
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Cengage Learning