Suppose we want to measure the width of an object and the size falls between two subdivisions of a ruler, the size can only be approximately known. To know the size to better accuracy a Vernier caliper is used. The working of the instrument is explained in this blog using a power point presentation, a YouTube movie, low and high resolution movies of the power point presentation.
Power Point presentation: VernierCaliper
YouTube : https://www.youtube.com/watch?v=NXQs2V-w-0s
Power Point video link (low resolution): http://vasundhara-raju.net/Physics/VC.mp4
Power Point video link (high resolution): http://vasundhara-raju.net/Physics/VC_rvas.mp4
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