Unit and Measurement | Chapter 1| Lecture 3 | Class 11 Physics | | Free Education скачать в хорошем качестве

Unit and Measurement | Chapter 1| Lecture 3 | Class 11 Physics | | Free Education

Unit and Measurement | Chapter 1| Class 11 Physics | CBSE Board NCERT | Free Education Dear Students, in this video we are going to study a very important topic History of the unit of length of chapter 1 Unit and Measurement from Class 11 Physics. Hope you find it helpful & interesting. Enjoy Learning! This Video is applicable for all students who are study in CBSE, ICSE and doing preparation for IIT. #freeeducation #study #free #unitandmeasurement #physics #class11 #class11preparation #cbsencert #cbse #derivedquantities #quantities 👉 Do watch the complete session to know about the Unit and Measurement, Don't forget to share this video with your friends and classmates. ✴️✔️ Do 𝐒𝐔𝐁𝐒𝐂𝐑𝐈𝐁𝐄 to the channel for more updates and hit that like button! ❤️ for daily updates (Turn on your notification 🔔 to get all updates before anyone!!) Here's the breakdown Unitless Derived Quantities The discussion begins with the differentiation between fundamental and derived quantities in physics, highlighting that kinetic energy is a derived quantity. The formula for kinetic energy is presented as 1/2 mv², where 'm' represents mass in kilograms and 'v' represents speed in meters per second. From the formula, the unit of kinetic energy is derived as kg·m²/s², which is recognized as a unit of energy. The refractive index is defined as the ratio of the speed of light in a vacuum to the speed of light in a medium, and its formula is given as c/v, where 'c' is the speed of light in vacuum and 'v' is the speed in the medium. When calculating the unit of the refractive index, both speeds cancel out, resulting in a dimensionless or unitless quantity. The discussion emphasizes that many physical quantities can be unitless, particularly when ratios of similar quantities are taken. Examples of unitless quantities are provided, including specific density, which is defined as the density of a substance divided by the density of water. Specific density is also shown to be unitless, as the units cancel out when the density of the substance is divided by the density of water. Supplementary Quantities The concept of supplementary quantities is introduced, focusing on angles as a physical quantity used extensively in mathematics and physics. The unit of angle is primarily discussed in terms of degrees, but the radian is presented as a more significant unit in physics. The relationship between arc length and radius is explained, leading to the formula for angle in radians as θ = l/r, where 'l' is the arc length and 'r' is the radius. Examples of calculating angles in radians are provided, illustrating how to convert between degrees and radians using the relationship between the two units. It is emphasized that angles can be considered unitless in certain contexts, particularly when derived from the ratio of two lengths. The discussion also includes solid angles, which are another type of angle that is also unitless but is given a unit called steradian. Systems of Units The lecture transitions to the systems of units, particularly focusing on the seven fundamental physical quantities and their respective units. Derived physical quantities are discussed, with examples such as force, which is calculated as mass multiplied by acceleration, leading to the unit of Newton (N). The SI unit system is highlighted, with its full form being the International System of Units, which is globally recognized for scientific measurements. Alternative systems such as the CGS (centimeter-gram-second) and MKSA (meter-kilogram-second-ampere) systems are briefly mentioned, noting their historical significance. The FPS (foot-pound-second) system is described, particularly its use in some regions for measuring force and length. The importance of SI units is emphasized, as they are the standard for scientific communication and calculations. Conversion between different unit systems is explored, with practical examples provided to illustrate how to convert length, time, and force between various units. Unit Conversion Examples Specific examples of unit conversion are presented, such as converting kilometers to meters and hours to seconds, reinforcing the concept of unit conversion in practical scenarios. The process of converting speed from meters per second to centimeters per second is demonstrated, highlighting the relationship between the two units. Further examples involve converting force from Newtons to dynes, emphasizing the need to understand the relationships between different unit systems. The conversion of work from joules to ergs is also discussed, providing insight into the historical context of these units. The importance of maintaining consistency in units during calculations is stressed, as it can significantly affect the results of measurements and calculations. 🔔 SUBSCRIBE and GET it FREE:    / @free-educations