The Total solution for NCERT class 6-12
Answer the following:
(a) You are given a thread and a metre scale. How will youestimate the diameter of the thread?
(b) A screw gauge has a pitch of 1.0 mm and 200 divisions on the circularscale. Do you think it is possible to increase the accuracy of the screw gaugearbitrarily by increasing the number of divisions on the circular scale?
(c) The mean diameter of a thin brass rod is to be measured byvernier callipers. Why is a set of 100 measurements of the diameter expected toyield a more reliable estimate than a set of 5 measurements only?
(a) Wrap the thread on a uniform smooth rod in such a way that thecoils thus formed are very close to each other. Measure the length of thethread using a metre scale. The diameter of the thread is given by therelation,
(b) It is not possible to increase the accuracy of a screw gaugeby increasing the number of divisions of the circular scale. Increasing thenumber divisions of the circular scale will increase its accuracy to a certainextent only.
(c) A set of 100 measurements is more reliable than a set of 5measurements because random errors involved in the former are very less ascompared to the latter.