Department of Mechanical Engineering
Student Study Guide semester 1 2019
Mechanics of Machines 11 (MECM 121/128/MEOM 102)
Subject:
NB:
MECM 121/128/MEOM 102 is contributing to the development of graduate attribute 1, 2 and 4
Lecturer:
Tel no.
E-mail
Mr. Z.M. Zondi
031 907 7229/10
Zakhele@mut.ac.za.
Venue
L13 Lecture theater
Lab
Applied Mechanics Laboratory
Course outcomes
Student who successfully complete this course will be able to
 Be able to understand scientific principles and apply them to the practice of engineering.
 Possess the problem solving skills, background and confidence necessary to educate themselves
continually throughout their careers.
 Able to apply the basic principles or measurement, data analysis and design experiments learned through
hands on laboratory experience.
 Be able to develop creative solutions to engineering problems
 Be able to work as part of the team.
weekly assignments / tutorials
Homework
Laboratory experiment:
Simple and compound pendulum, moment of inertia, belt friction and conrod experiment
Test:
Class test 2 main test
Exams:
3 hour
Pre requites engineering mechanics I Mechanical Engineering Drawing I and Mathematics I.
GRADUATE ATTRIBUTES
Graduate Attribute 1: Problem solving
This graduate attribute is about applying engineering principles to systematically diagnose (identify) and solve well-defined
engineering problems.
Well defined
MOMENT OF
INERTIA
Learner objectives
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VEHICLE
DYNAMICS
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Specific learner outcomes
Graduate
Attributes
On completion of this chapter the learner should be able to:
 Define moment of inertia and radius of gyration.
 Derive moment of inertia of standard bodies like
rectangular plates, triangles, rectangular blocks, solid
disc etc.
 Apply theorem of parallel axes.
 Apply the theorem of parallel axes, in calculations of
moment of compound bodies
4
On completion of this activity the learner should be able to:
Driving torque,
acceleration, work ad
 Describe tractive effort, tractive resistance, rolling
power.
resistance and gradient resistance on a vehicle.
Tractive effort, rolling
 Derive the equivalent moment of inertia at the wheels
resistance, transmission
of a vehicle, i.e. 𝐼𝑒 + 𝐼𝑤 + 𝑛2 𝐼𝑒 .
efficiency.
 Derive the formula 𝑇𝑤 = (𝑇𝑒 − 𝐼𝑒 𝛼𝑒 )𝑛. ƞ − 𝐼𝑤 𝛼𝑤 be
Maximum possible
able to use it.
tractive effort.
 Calculate the equivalent inertia of all moving parts in a
Normal reactions on
vehicle at the wheels and vice versa.
road wheels.
 Calculate the tractive efforts at the wheels of a vehicle
Maximum possible
when a certain engine torque is given
acceleration and
 Calculate the normal reactions at the rear and front
retardation
wheels on a vehicle.
 They must be able to calculate the maximum possible
acceleration or retardation if the vehicle is driven by
front, rear and all the wheels.
4
Statics and Dynamics.
Geometry, dimensions
and relative motion.
Mass, force, weight
and motion.
Newton’s laws of
motion
Moment of inertia
Theorem of parallel
axis
HOISTING AND
HAULING
MACHINES.

Types of hoists,
functions and typical
applications.
Equivalent moment of
inertia for geared
systems.
Power required raising
or lowering a load
On completion of this activity the learner should be able to:
 They need to be able to draw all the forces (free body
diagram) acting on the object
 Acceleration.
 Find tension in the cable of a hoist
 Find the acceleration and retardation of a hoisting
system.
 Find the total torque applied on a system to a give a
certain acceleration.
 Find the total power developed by a motor on a system
4
Types of brakes and
typical applications.
Theory and
calculations
On completion of this activity the learner should be able to:
 Find the ratios between the tight and slack sides of a
flat and V-belt.
 Find the angle of contact on a belt drive and band brake
 Find d tension in the tight and slack sides on a belt
drive and band brake.
 Find the initial tension in a belt drive
 Find the power transmitted in a belt drive.
 Find the torque applied on a band brake and power
dissipated due to friction
4
They need to know different On completion of this activity the learner should be able to:
types of clutches
 Calculate the maximum torque that can be transmitted
by the clutch.
 Calculate the force needed between the friction faces.
 Calculate the maximum pressure between the friction
faces
Conservation of energy is On completion of this activity the learner should be able to:
important for this section
 Find the kinetic energy of a rolling body without slip at
a certain speed.
4
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
BELT DRIVES
AND BAND
BRAKES
CLUTCHES
ROLLING
BODIES
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4
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Find the rate of change of kinetic energy of a rolling
body.
Find the minimum coefficient of friction for a body to
roll down a given inline without slip
Textbook and software:
Mechanics of Machine by J Hannah and RC Stephens, Elementary Theory and Examples;
Arnold, Fourth edition. Students are also given prepared notes with questions for tutorials.
Students can also use the library to look for textbooks which are related to the sections that they
covered in class.
Textbook:
Theory of Machines written by R.S. KHURMI and
J.K. GUPTA. You are advised to use the library for relevant text books pertaining the work that is
covered in class
Laboratory Work:
Students will be divided into groups, the size of the group depending on the total number of students in the class.
Each group will do 2 practicals. Each group must submit a report on each practical which must be handed
to the lecturer concerned not later than one week after the particular practical session. Questions on the
laboratory work can be included in the second test or in the final examination. Laboratory work is
developing attribute 4.
Final Mark:
The final mark = [0,6x examination mark] + [0,4x course mark]
As an example, if the above student obtained an examination mark of 57%, then the final mark will be:
[(0,6x57) + (0,4x60)] = 58.2 %.
Mechanics of Material 1 third edition- EJ Hearn
Mechanics Materials 7th edition - J.M. Gere and B J Goodno