How gravity and friction affects motion
- 1. HOW GRAVITY AND FRICTION AFFECTS MOTION
- 2. You have learned in the previous lesson that friction is a factor that can affect the motion of an object. Sir Isaac Newton formulated the Three Laws of Motion explaining how this happens. These are the Laws of Inertia, Law of Acceleration and the Law of Interaction.
- 3. In today’s lesson, we will learn about the other factor that affects the motion of an object.
- 4. Have you ever wondered why the objects we throw upward tend to fall every time? That is because there is an invisible force that causes every object to fall to ground. That force is what we call gravity. We cannot see it. We cannot even smell or hear it but we can feel it. If you are sitting upright in your chair right now, that is because of the gravity.
- 5. In short, gravity is useful in our everyday life. This chapter tends to explain on how gravity affects the movement of different objects and relate it to our everyday activities.
- 6. After this lesson, you are expected to understand how gravity affects the movement of different objects.
- 7. ACTIVITY 1: What I know https://docs.google.com/form s/d/e/1FAIpQLSdXz39mIn40 Wq5eBScnOcUCXqpEuAlYZ YMqJEY4Pq1X9cii0g/viewfor m?usp=sf_link
- 8. What was your score? If you got all the answers correct, congratulations! It shows that you have a wide range of knowledge when it comes to our topic for today. You may still review this topic and learn new things ahead.
- 9. If you did not get a high score, no worries. This module will help you learn more the concept that you may eventually use in your daily life. Study carefully this topic and you will be able to answer all questions in the activities that lie ahead. Are you ready? Can an object move by itself? Why does object move? It is very simple yet seemingly foolish question. But motion is an important part of your life. Without motion, no work would have been done. Suppose you want to move your pencil on the table. Name some ways by which you could move it.
- 10. Besides the Three Laws of Motion, Sir Isaac Newton also developed another law regarding motion. This is the Law of Gravitation. It is based on the nature of the gravity, a force that makes everything fall. This law states that every particle and object in the universe attracts every particle and object. The amount of gravitational attraction depends on how far the objects are and how much mass the objects have. It is greater when the objects are close together and have greater mass.
- 11. What happens when objects of different weights are dropped from the same height at the same time? Of course, you would assure that the heavier object would hit the ground first. But Galileo’s famous experiment proved it otherwise; - both objects struck the same time. Why?
- 12. Provided air resistance is not considered, gravity causes objects to constantly accelerate at 9.8 meters per second for each second of fall. It is the same no matter what the mass of the object may be.
- 13. But air resistance balances the gravitational attraction of the earth on any falling object. The faster an object falls, the greater is the air resistance. Air resistance is greater as the speed is increased. Have you ever held your hand out of the jeepney traveling at about thirty kilometers per hour? Do you feel your hand being pushed in the opposite direction from the direction at which the jeepney is traveling?
- 14. As jeepney increases its speed, it would be difficult for you to keep your hand in one direction. Air resistances make it so. It also makes objects such as feathers, Ping-Pong balls, and sheets of paper fall more slowly from high places than objects such as marbles, ball bearings, and baseballs.
- 15. ACTIVITY 2: “WHICH FALLS FASTER?” Direction: Answer the following question. 1. Imagine you have a coin and a feather and you drop it at the same time in the same height. Which one will get at the ground first? Why is that so?
- 16. ACTIVITY 3: “PAPER RACE!” Crumple a sheet of paper. Get another sheet of paper but this time, do not crumple it. Drop both sheets of paper at the same time at the same height of a meter. Which paper hits the floor first? Why?
- 17. ACTIVITY 4: “EXPERIMENT TIME” Materials: Feather, coin, paper and stopwatch. Let’s do these way: 1. Throw the piece of paper up to the air without hitting your ceiling. Start measuring the time when it leaves your hand and stop the time when it reaches the ground. 2. Throw the feather up to the air without hitting your ceiling. Start measuring the time when it leaves your hand and stop the time when it reaches the ground.
- 18. 3. Throw the coin up to the air without hitting your ceiling. Start measuring the time when it leaves your hand and stop the time when it reaches the ground. 4. Fill up the table below with the data you have gathered.
- 20. Let us answer this: 1. Which material lands the ground the fastest? How about the material that lands the slowest? 2. Which materials show the presence of air resistance? How do you say so? 3. What do you think are the reasons why the paper, coin and feather did not hit the ground at the same time?
- 21. ACTIVITY 5: “ANALYZE ME!” Look at this skydiver who is trying to regulate his speed. When is he falling fastest? Falling slowly? Why?
- 23. ACTIVITY 7: “THINGS I LEARNED” With all the things you have learned, what do you think are the importance of understanding gravity in the motion of objects?
- 24. The learners, in their notebook, journal, or portfolio will write their personal insights about the lesson using the prompts below. I understand that _____________. I realize that _________________.