 channel for physics please subscribe my channel hello everyone and welcome back to another episode of physics partner today I brought some information about one majoring device known as vernier caliper it's actually an instrument for making very accurate linear measurement and so introduced by 1631 so it utilizes two graduated scales the bigger one is a main scale and the smaller one is considered as auxiliary scale or it's also called vernier scale the scale that slides parallel to main scale that enables reading to mate for example, if you can move it like this you can see the scale which is sliding parallel to the main scale and enables reading to be made in the fraction of division on the main scale. So, vernier scales basically are widely used in scientific laboratories and in manufacturing for quality control measurements vernier calipers also used in education for almost all famous curriculum as a measuring device. So, let explore more about let me make it more closer I would like to share the parts of this vernier caliper. So, you can see in the screen the main one is considered as main scale as I told you before and this small one is called vernier scale and this and this is same thing actually both are vernier scale, but the difference you can see it's from this point let me make it more closer to you the inches here it is 1 over 128 inches and 0.05 millimeter here down. So, mostly measurement is done by 0.05 millimeters which is actually a least count of this device what do you mean by the least count. So, for example, your wall clock or your watch cannot measure less than second is considered as a least count. Let us talk about more parts. So, you have you can see the jaws and the upper jaws and the lower jaws they are used to find out the length of something when you need a very accurate reading in engineering for a small length you are using vernier calipers. Similarly, you can see there is a upper jaws also which is used to find out the internal diameter and external diameters I am going to show you the four uses of vernier calipers. So, the first use is to finding a length of something now you have vernier calipers and you want to find the length of something you can use vernier calipers this is the first use. Secondly, you can find the external diameter of any object for example, you can see here you can find an external diameter of something and similarly the third use can be the internal diameter of an object. So, you can find an internal diameter of an object also and finally, the depth of something. So, four basic use of vernier calipers measuring length internal diameter external diameter and the depth of an object. So, this is the purpose of the vernier calipers let us see how can we calculate before going for calculation I would like to share this also. Nowadays, there are so many advanced digital vernier calipers or other vernier calipers are available which can show you the readings directly. Here, I have made a small program. So, this can calculate our measurement. So, I will show you how to calculate the measurement let me make it more closer for you again and let me put something inside. So, explain how to measure it. So, I have fixed an object here you can see that. So, let me explain the numbers which are appearing on the top of the screen. So, 20 is actually the main scale reading you can see the blue arrow which is showing a 0 here on vernier scale and before this is only 20. So, on main scale what we covered is only 20 which is the main scale and the blue one is the subdivision of 20. You can see there is one which is now 20 and 21 and what is 0.25? 0.25 is the most matching line here which shows let me make it more closer to you. So, what is 0.25 here? 0.25 here is most matching line of vernier scale with the main scale. So, you can see here 0, 1, 2 and 2.5. So, because it is in millimeter and 0.05 is a least count. So, it is considered as 0.25 this line is completely matching with the main scale. So, first of all the main scale reading which is 20 and it crosses 1 also. So, 21 the blue line. So, 21 and you have to see the most matching line which is 0.25. So, this will be the reading 21.25 will be the reading on this scale. 21.25 will be the reading which is showing the length of this object is 21.25. So, I hope you understand that it is very easy, very simple, very precise to measuring device to finding the length internal diameter, external diameter and definitely you can find out the difference between internal diameter and external diameter to check the width of any object. In the last I would like to discuss some precautions you have to take while using vernier caliper. In exam usually the examiner ask about the precautions as well. So, remember number one is the object should also always be gripped gently between the jaws. This is extremely important while measuring object which are easily deformable for example, wires. Second thing is before taking any measurement make sure that vernier caliper does not have a zero error. It means it should be fixed completely the lines should be matching with the main scale and vernier scale lines should be completely match. Number three the surface of the object which need to be measured should be clean and dried. The lower jaws should be opened slightly and their inner surface should be clean and dried with. So, let us see some applications of vernier caliper in industries and in schools. So, you can use it in different places as you can see on your screen. So, that's all for today. This is a small video for vernier caliper. What is this device, what is it used for and how you can use it for the measurement of different objects in terms of their length, internal diameter, external diameter and depth. Thank you very much for watching and listening. Take care of yourselves. See you in the next video. Take care.