Engineering Questions with Answers - Multiple Choice Questions
Machine Drawing MCQ – Methods of Size Description & Drawings Preparation – 1
The system in which variation in size is accepted is termed as ___________
a) Limit system
b) Tolerance System
c) Limit and tolerance system
d) Variable system
Explanation: In production line since it is impossible to make a part of exact drawing due to the inaccuracy of machine, setting and measurement thus some deviation is allowed in given maximum and minimum limit. The system in which this variation is accepted is termed as a Limit system and the allowable deviation are termed as tolerances.
What is the basic size?
a) Size calculated by the design engineer to withstand the stress coming in component
b) Size exactly of that of given object under consideration
c) Size of the object with given deviations
d) Size with which a job come out of the shop
Explanation: A design engineer calculate the size of an object using theory of failure and then give the size to the object with which an object of given material can withstand the stresses coming in the component, this size is termed as basic size. It is the size to which limits of tolerance are assigned.
What is the actual size?
a) Dimension of a component on paper
b) Dimension of the component manufactured
c) Size of the component as per theory of failure
d) Size of the object with all the tolerances
Explanation: The actual size the dimension obtained of a product when it is manufactured and come out of the shop. It may not be of the same size as given on the paper and comes in the dimension between the given tolerances. Simply the size of the manufactured component is actual size.
Tolerance is ___________
a) Difference between the basic size and maximum limit
b) Difference Between the minimum and basic size
c) Difference between the maximum and minimum limit size
d) The maximum size of the component allowed
Explanation: Tolerance is the difference between the maximum and minimum deviation that can be given to a component size thus tolerance is defined as the difference between the maximum and minimum limit size.
Cost of manufacturing is ____________
a) Inversely proportional to the amount of tolerance specified
b) Directly proportional to the amount of tolerance specified
c) Does not depends on tolerance specified
d) Does depends non-linearly
Explanation: Generally tolerance is provided in the narrow region, however, narrower the tolerance more difficult it is to manufacture a component thus the cost of manufacturing does depend on the tolerance specified and it is inversely proportional t0 the tolerance provided.
Explanation: Since there is given with the deviation on two sides this means this is bilateral and as these deviations are not equal that tells us that the type of tolerance is unequal bilateral thus option c is the correct answer for the given figure.
Explanation: Since the given maximum and minimum tolerance are to be taken in consideration
Minimum dimension of A=120 – (40+.2) – (40+0) = 39.8
Maximum dimension of A= (120+.6) – (40 – .2) – (40 – .3) = 40.1
So only 40.00 lie in between 39.8 and 40.1.
Explanation: Since the size of a component can lie from the maximum limit to the minimum limit.
Here, Minimum size = Basic size -lower tolerance
=35.79 – 0.3 = 35.49.
What is the type of the tolerance provided here and dimension of the given object in the figure below?
a) Equal bilateral and maximum size of 50.05
b) Equal bilateral and minimum size of 50.05
c) Equal bilateral and minimum size of 49.95, maximum size of 50.05
d) Equal unilateral and minimum size of 49.05, maximum size of 50.05
Explanation: Since the given dimension is with deviation on both side equal to the 0.05 and have the basic size of 50 thus the minimum size is 50 -.05 = 49.95 and maximum size is 50+0.05 = 50.05 and the type of the tolerance given here is equal bilateral.
The type of the dimension of the given object in the below figure is __________
a) Basic size equal to 50.00 and tolerance +.05 and -.05
b) Limits where maximum limit is 50.05 and minimum limit is 49.05
c) Basic size with the tolerance
d) Dimension of rectangle having 50.05 and 49.98
Explanation: The given dimension are the limits written one above another where upper limit is written above the lower limit, here maximum dimension is 50.05 and minimum dimension is 49.98. If we were to calculate size assuming basic size equal to 50 then tolerance are equal to 50.05 – 50 = +0.05 and 49.98 – 50 = – 0.02.