It was Saturday and the last exam for Kumar and all of his friends. The next day, Sunday, all the boys planned to play cricket because they wanted to celebrate finishing exams. Everyone wrote the last exam very well and were very excited to play cricket the next day.
Kumar woke early that day and got ready faster than usual; his mother was shocked to see him get ready on SUNDAY. But Kumar felt very tired after waking up. He was not having any fever or health problem. Still, he decided to go and play. The match had started and Kumar was batting. Kumar’s friends played very well and there was a very less score to chase in the last over in which Kumar was batting. Kumar hit the ball far and started to run to the other side but he wasn’t able to. He started panting but yet decided to run to the other side because he wanted to win and finally, they won. Even though Kumar was feeling tired he gave his best and ultimately his hard work gave him a good result.
Why do you think Kumar was tired?
What will happen if someone is tired?
What do you mean by being ‘tired’?
When we are tired, we are not able to work properly. It will be very hard to do something when we are tired. That is why we take rest by sleeping so that we don’t feel tired to do any work that we have to. Kumar was studying for his exams for a very long and after so much hard work he did not sleep well the next day. His body did not get enough rest to play as he would play normally but was tired.
When we are tired, what do we don’t have to do any work?
We don’t have the energy to do the work or play or study or do any common things. And that is why taking rest is very important for us.
Contents
What is Energy?
Energy is the ability to do any work at any point in time. The ability to move an object, throw an object, drive the car, ride a bicycle, play games, to study is called energy. Energy is of many forms some we can see and some we don’t. But, energy is everywhere around us.
1. Heat energy
Objects like the utensils used to cook food also get hot while cooking the food. The ice-cream in the refrigerator gets freezing cold inside. This being hot or cold of any object tells us how much heat energy the object has. If any object has less heat energy, it is cold. If any object has high heat energy, then it is hot. The main source of heat energy for us is the sun. The light from the sun gives us heat because light has energy in it and when this light reaches the earth, the earth becomes hot.
2. Light energy
Light is one of the very basic forms of energy. We get the heat from the sun in the form of light. Light energy enables us to look at the world around us. Without light, we cannot see anything. We can get light in a natural way, that is, by sun and in artificial ways, that is, by light bulbs and electricity.
3. Sound energy
Sound is also one of the very common forms of energy we can experience every day around us. Sound energy is created by the movement of very very tiny particles in the air which move very fast, when these particles move very fast, we get sound.
4. Potential & Kinetic energy
Potential energy is the energy that is stored inside a body that is at rest. And kinetic energy is the energy that a body has when it is moving.
Imagine a vehicle moving up a small hill. As it moves, it has kinetic energy. At the top of the hill, the car stops and has potential energy. In simple terms, a moving body has kinetic energy and a body at rest has potential energy.
Quiz
1. What type of energy does the sun provide?
- Heat energy
- Light energy
- Heat and light energy
- Kinetic energy
2. Sun is the reason why the earth heats up.
- True
- False
3. The energy an object has when it is moving is called _____
- Potential energy
- Kinetic energy
- Sound energy
- The object does not have any energy
4. We need ______ to do different kinds of works
- Money
- Water
- Energy
- We don’t need anything to do a work
5. We can get heat energy from _____
- Burning wood and fuel
- Friction
- Sun
- All the above