Meaning of Conversion of Units
In physics, we usually need to convert units from one standard to another, such as mile to meter, hour to second, meter to an inch, feet to meter, kilogram to the gram, and so on. You'll need to know how to convert meter to the inch, a kilometer to a mile, and so on, such as 1m = 39.37in or 1km = 0.6214mi.
When the quantity expressed is not in our familiar format, such as when we want to convert units to SI units, unit conversions are required (in physics, we always convert units to SI units). We may not be familiar with the value of a physical quantity when expressed in a different unit format. Instead, you might want to add the values in a calculation that involves another unit. In this article, we have provided different conversion units for measuring different parameters. Let us start by understanding the conversion of units in the coming section.
Conversion of Units
The primary focus of this chapter is to tackle the conversion of units of measurement of various quantities. However, before we start, it is essential to understand fundamental and derived physical quantities and their units.
To learn how to convert units of physical quantities, it is necessary to be aware of the terms–dimensional formula and dimension equation. First, check these details about fundamental and derived quantities.
Fundamental Quantities and Derived Quantities
All measurable physical quantities can be primarily classified into two types, which are –
Fundamental Quantities
A small group of physical quantities are considered as fundamental quantities or primary quantities which are used to derive other physical quantities.
For Example: Mass, time, length, electric current, the luminous intensity of light, temperature, amount of substance are all fundamental quantities.
Derived Quantities
Also referred to as secondary quantities, derived quantities are formed from primary or fundamental quantities.
For Example: By dividing distance by time, we can calculate the speed of an object. Hence, speed is a prime example of a derived quantity.
Additionally, if we multiply the breadth, length and height of an object, we get to derive the volume. So volume is also another example of a derived quantity.
Fundamental and Derived Units
Units selected for primary physical quantities are known as fundamental units. Meanwhile, those units which are formed with the help of fundamental units are termed derived units.
For Example: Speed is a derived quantity whose unit is determined as distance/time, i.e. metre/second. Here, you can notice that metre and second are fundamental units while the unit of speed, i.e, metre/second, is a derived unit.
A Complete Unit Conversion Table
To solve numerical problems in the case of unit conversion questions in physics, consulting a tabulated form of unit conversions is highly important, especially for beginners.
Several tables containing the unit conversion formulas are given below, which sum up almost every essential physical quantity. Each table contains various units and their conversions of a specific physical quantity, fundamental or derived. Let us now learn unit conversion with the help of the unit conversion table.
Basic Unit Conversion Table – Length
Unit Conversion List – Mass
Units of Measurement Conversion Table – Volume
Units and Conversions – Time
Unit Conversion Table – Energy
Unit Conversion Table- Power
Numerical Problems from Unit Conversion Tables
Numerical problems with the conversion of units in physics are quite common in exams. For example, the following question is frequently asked –
1. State the Relationship Between Dyne and Newton?
Ans: As we know, dyne and Newton are units of force. The dimensional formula of force is [MLT-2].
Hence, 1 Newton = 1 x kg x m x s-2 = 1 x 103 g x 103cm x s-2 = 1 x 106 g x cm x s-2
So, Newton = 106 dyne.
At Vedantu, we hope that this discussion on the Conversion of Units will help you attain high marks in the upcoming physics exams. Moreover, make sure to download our Vedantu app to access study materials and online classes easily.
FAQs on Conversion of Units
1. Name Four Fundamental Quantities in Physics?
Four fundamental quantities in physics are mass, length, time, temperature, etc.
2. What is the Difference Between One Pound and One Ounce?
One pound equals to 4.53 x 102 grams while one ounce can also be measured as 0.283 x 102 grams
3. How Many Litres of Diesel Will Make One Gallon?
0.03785 x 102 liters of diesel will make one gallon of diesel.
4. What do you mean by unit conversion factor?
Unit conversion is a method of expressing the same property in a different measurement unit. Time, for example, can be expressed in minutes rather than hours, and distance can be changed from miles to kilometers, feet, or any other unit of measurement. Measurements are given in one set of units, such as feet, but are needed in the other, such as chains. A conversion factor is a numerical equation that enables an equal exchange of feet to chains.
5. Is it necessary to convert the units? Why?
Yes, it is necessary to convert the units. Sometimes, the units used for measurements do not match measurement preferences and convenience and the standards specified for certain processes and applications. It is important to convert these units to a level that can be directly understood and applied correctly. To better understand this sentence, let us consider the example of a person who is only familiar with the metric system. This person cannot easily calculate the height of a 25-foot tree. Converting 25 feet to meters will help people better understand the height of the tree.
6. How to learn topics like Conversion of Units in physics effectively?
Apart from theory, physics also has mathematical problems, which can be challenging at times. However, one can surely be a champion by following certain methods. Here are a few tips that will help you understand and learn physics effectively:
Theories are one of the main aspects of physics. It is essential to understand the basic concepts along with their principles.
Memorize the equations. The equations are used in many questions. If you memorize them thoroughly, you can use them in the right place.
Analyzing the problem is necessary. Students feel that solving questions in physics is tough, but once you go through the question, analyze it, you will find it easier.
Use correct units in the answer. It is essential to put the right units in your answers; if you want to receive credits for the problems solved.
Pay attention in your class, understand the concept, and make proper notes.
Physics is the same as maths in terms of problem-solving. Students need to practice a lot of questions. Not only will it help you to solve the problems, but also get a clear understanding of the concept.
To learn physics quickly, online lectures are also an option. Many online websites provide free video lectures, such as Vedantu. The concepts are explained to students in an easy way.