Force And Motion – Session 1

Physical quantities are the things that can be measured. For example, if you want to know the distance from your house to the park, you need to measure the distance. If you want to bake a cake, you need to measure the ingredients. All these measurements are the physical quantities. Some examples of physical quantities are length, volume, time and weight.

Measurement is an essential part of understanding physical quantities. Without measurement, we would have no way of knowing how much of something we have. We would have no way of knowing how far apart things are. Measurement is also important in everyday life. For example, when baking a cake, precise measurements of ingredients are necessary to ensure that the cake is baked correctly. In construction, the accurate measurements are crucial for ensuring that the buildings are safe and stable. In sports, timing and distance measurements are used to determine winners and losers.

Let us first understand the concept length. Length is a measurement of distance between two points. It can be measured using units such as centimeters, inches or yards. For example, the length of a pencil can be measured in centimeters. The length of a football field is measured in yards. The length can be measured using an instrument called the ruler. With the help of aruler can you tell what is the length of your pencil?.

One good example of measuring length is when you are shopping for clothes. You need to know your own measurements in order to find clothes that fit properly. This involves measuring the length of your arms, legs, and torso. Another example is when you are making furniture. You need to measure the length of the pieces of wood in order to cut them to the correct size. Without understanding the length, we could end up with furniture that does not fit in our space or furniture that is small.

The length is important in many professions such as architecture, engineering, and construction. These fields of study need precise measurements to ensure safety and functionality. Imagine what would happen if a bridge is built without accurate length measurements? It could be disastrous.

Imagine you have a box. Volume is all about how much space that box can hold inside. It is like asking, how much stuff can I put in this box? Now, let us think about it in terms of water. Imagine you have a glass of water. The amount of water that can fit inside the glass is its volume. It tells you how much water the glass can hold.

Volume is usually measured in the cubic centimeters. It is called cubic because it is like measuring in three dimensions. These three dimensions are length, width, and the height. Everything around us has three dimensions. For example, a box has a length, width and height.

Let revisit the box example. Let us say the box is ten centimeters long, five centimeters wide, and three centimeters tall. You can find its volume by multiplying those three numbers together. So, the box can hold up to one hundred and fifty cubic centimeters of the stuff. One hundred and fifty cubic centimeters is the volume of the box.

In real life, volume helps us figure out how much space something takes up or how much it can contain. For example, when you fill a glass with juice, you can use the volume to know how much juice the glass can hold. So, the volume is all about measuring how much space something occupies.

Imagine you are going to a park. Can you tell how long it will take for you to reach the park? We can measure it with the help of time. Time is also a physical quantity. Imagine time as a way to keep track of events and moments in our lives. When you wake up in the morning, the time tells you that it is a new day. When you meet your friends for lunch, the time helps you all coordinate and be there at the same moment. Without time, you might miss meeting your friends for lunch!.

We can measure the time in different units, similar to how we measure the length in centimeters. The basic unit of time is a second. Second is like the rhythmic heartbeat of a clock. It can be grouped as minutes, hours, days, weeks, months, and years.

We use a clock or a stopwatch to measure the time. Imagine you are going to the school. You want to know the time it takes for you to arrive at school. How will you measure this time? You will take a stopwatch. Start the stopwatch when you start your journey towards school. Stop the stopwatch when you reach at school. This way, you can measure the time between two events.

Time is not something that we can see or touch. However, we can feel the presence of the time in our everyday lives. You can think of it as an invisible force that keeps everything moving forward. We cannot make it slow or speed it up. It keeps flowing at its steady pace.

We can measure the distance between two objects with the help of the ruler. Can you tell how far is the sun from us? We cannot measure the distance between sun and earth with the help of the ruler. Then how can we measure such a long distance?.

We can measure such long distances with the help of the time. For example, the light from the sun reaches the earth in eight minutes. We can say that the distance between the sun and the earth is eight light-minutes.In same way, let us say that it takes two years for the light to travel from the star to the earth. Therefore the distance between that star and the earth is two light years.