Design of Machine Elements MCQs | Page - 2

 loose tolerance results in increase in cost, assembly problems and poor performance of the product. tight tolerance results in unnecessary machining and inspection time.

 in establishing of realistic specifications, control charts are considered as a good guide for the design office. quality

 there are two approaches for deciding of tolerances and shafts i.e. statistical and complete interchangeable approach. there is no risk is taken about a single non-conforming assembly in complete interchangeable approach.

 beam is said to be uniform strength if at every section along its longitudinal axis, the bending stress is same.

 the stress is directly proportional to the load and here the load is in terms of bending. so the stress is directly proportional to bending.

 when there is an eccentric load it means that the load is at some distance

 when a beam is in bending the layer in the direction of bending will be in compression and the other will be in tension. one side of the neutral axis will be shortened and the other will be elongated.

 from the bending equation m/i

 if we resist to expand then only stress will develop. here the bar is free to expand so there will be no stress.

 area of the cross section of column = π/4 (0.302 – d2) m2