Centro, Santo Tomas, Isabela 3327 300606@deped.gov.ph SCIENCE 9 Detailed Lesson Plan April 23, 2024 I. OBJECTIVES: a. Content Standards: The learners demonstrate understanding of projectile motion, impulse and momentum, and conservation of linear momentum. b. Performance Standards: The learners should be able to propose ways to enhance sports related to projectile motion. c. Learning Competencies with Code: Relate impulse and momentum to collision of objects (e.g., vehicular collision) (S9FE-IVb-36). At the end of the discussion, students are expected to: a. infer that the total momentum before and after collision is equal; b. describe how a balloon rocket works and how conservation of momentum explains rocket motion; and c. relate impulse and momentum to collision of objects (e.g., vehicular collision); II. SUBJECT MATTER: A. Topic B. Reference C. Materials pinch of flour III. PROCEDURE Teacher’s Activity A. Motivation : Conservation of Momentum : Science 9 Module 1 pp 251-253 : Long shape balloon, straw lace, tape, paper clip, straw, Student’s Activity Yesterday we had an outdoor activity entitled balloon rocket. What were the factors again that affect the force of impact on moving objects? Mass, sir. What about the mass of the object? The heavier objects tend to have greater impact force. Precisely! What else aside from the mass of an object? Time, sir. Aha! Can you elaborate more about it? Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” The lesser the impact, the shorter the time of the objects being collided. 1 Therefore, is it directly proportional or inversely proportional? Inversely proportional, sir. Good. I believe, we enjoyed performance task yesterday, right? our Yes, sir. We want more, sir. Oh really? Yes, sir. B. Presentation If that so, we will play a game called, “identify me.” Letters B and C, sir. Okay, let’s reveal! Great! How about, Letters A and D, sir. Alright! Let’s reveal! Push and pull, sir. What do you think is our topic for today? You have a point. These are one of the characteristics of our topic. Therefore, our lesson today is all about conservation of momentum. Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” 2 C. Discussion Activity: Balloon Rocket For us to know more about the conservation of momentum, we will be having our activity entitled, balloon rocket. Kindly bring out the materials needed for this activity. Groups 1, 2, and 3 will check each other’s materials if completed. And so, with (Each group is checking the materials) groups 4 and 5. Give me a thumbs up mark if the group you’ve checked is complete. (Everyone is showing their thumbs up) Amazing! You are all responsible for today, class! This time, I want all of us to go outside of this room to perform the activity entitled, balloon rocket. Group 1, please read step 1. 1. Stretch the string over two posts. You can use chairs as posts. Make sure that the string is taut. I will give you 1-minute to set-up your posts. (Students are setting up their posts) You’re all doing good. Group 2 kindly read step number 2. 2. Inflate the balloon. Twist the open end and temporarily secure it with a paper clip. You inflate the balloon carefully, okay? Yes, sir. Next, group 3, kindly read step number 3. 3. Tape the straw to the balloon such that it is aligned with the balloon’s opening (see Figure 20). Look at your books on page 266. It should be like that. Lastly, group 4, kindly read step number 4. 4. When the balloon is stable, release the clip and let the air out of the balloon. The group with the farthest balloon rocket to go will win the game and will receive a certificate and 30 points to performance task. Meanwhile, 29 points for the 1st runner-up, 28 points for the 2nd runner-up, 27 points for the 3rd runner-up, 26 points for the 4th runner-up and the shortest range that the balloon can go receive 25 points. Please be guided to the following questions and copy this in ½ sheet of paper, Q1. What can you say about the initial momentum of the system before releasing the air from the balloon? Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” 3 Q2. What did you observe after releasing the air from the balloon? Q3. What is the direction of the balloon compared to the direction of air coming out from the balloon? Q4. How do their momenta compare after releasing the air? Q5. From your answer in Q4, how does the velocity of the air that is pushed out of the rocket compare to the velocity of the balloon rocket? Understood? Yes, sir. On my cue. The battle begins in 3, 2, 1 go! (Students are performing the activity) Group 2 wins the game! Congratulations! Let’s go back to our questions. Group 1, kindly read and answer question 1. Okay, do you have the same answer with group 1? Q1. What can you say about the initial momentum of the system before releasing the air from the balloon? -the initial momentum of the system before releasing the air from the balloon is zero. Yes, sir. Group 2, kindly read and answer question 2. Q2. What did you observe after releasing the air from the balloon? -after releasing the air from the balloon, the inflated balloon shrunk, as the rushes out, the balloon moves. Great! As long as there is the word shrunk, check it! Group 3, kindly read and answer question 3. Q3. What is the direction of the balloon compared to the direction of air coming out from the balloon? -the balloon and the air coming out move in opposite directions. Good! How about the other groups, do you have the same answer with group 3? Yes, sir. Okay. Group 4, kindly read answer question 4. Q4. How do their momenta compare after releasing the air? -they are in the same magnitude. Precisely! Last group, kindly read and answer question 5. Q5. From your answer in Q4, how does the velocity of the air that is pushed out of the rocket compare to the velocity of the balloon rocket? -the velocity of the air is greater than that of the balloon. I have here a sample word problem and let us try to solve. Two ice skaters stand Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” 4 together. They "push off" and travel directly away from each other, the boy with a velocity of +1.50 m/s. If the boy weighs 735.0 N and the girl, 490.0 N, what is the girl's velocity after they push off? (Consider the ice to be frictionless.) The said weight will be converted into mass by using this formula, where: w=weight m=mass g=gravity (9.8 m/s2) Given: wboy=735.0 N wgirl=490.0 N vboy=+1.50 m/s vgirl=? 𝑤 mboy= 𝑔 735 𝑁 mboy=9.8 𝑚/𝑠2 mboy= 75 kg 𝑤 mgirl= 𝑔 490 𝑁 mboy=9.8 𝑚/𝑠2 mboy= 50 kg Re-write these computed masses in this table, Mass Velocity Boy 75 kg 1.50 m/s Girl 50 kg ? The velocity of the girl is unknown. We will the formula, Total Initial Momentum=Total Final Momentum 0= pboy + pgirl -pboy = pgirl -(mv) boy = (v) girl -112.5 kg m/s=50 kg (v) girl 50 kg 50 kg -2.25 m/s= (v) girl This means that, the girl moves with a velocity of 2.25 m/s opposite to the direction of the boy. Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” 5 D. Application Activity: Lights, Camera, Action! Direction: Think of a scenario that has something to do with conservation of momentum. I will only give you 1 minute to brainstorm and 20 seconds for presentation of what you wanted to act. 20 is the highest possible score points. Here are our criteria for your activity: Application of conservation of momentum- 10 Creativity- 5 Discipline- 5______ 20 points Your 1 minute starts now! (Students are brainstorming) Time is up! Group 1 will be the first one to present followed by groups 2, 3, 4, and 5, respectively. E. Values Integration In your sticky notes, I want you to make 2 to 3 sentences reflection about, why do we need to know the conservation of momentum in real-life? You post on the wall and I will give at least 2 minutes to do the task and your timer (Students are doing their reflections) starts now! F. Generalization To summarize everything we learned for today, what law of motion is in line of our topic today? 3rd law of motion, sir. Okay, good! By whom again? Isaac Newton. What does the law of conservation of momentum states? Sir, the total momentum before a collision is equal to the total momentum after a collision. Correct! How about, if two objects collide or explode, they will experience what? The same force for the same amount of time, sir. In our computation a while ago, how do we get the mass? Quotient of weight and gravity. Precisely! Are now ready for your last activity today? Yes, sir! If that so, we’ll be having an online quiz! Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” 6 IV. EVALUATION Activity: Quizizz Game Direction: In the same groupings, students will log in their accounts in this link, https://quizizz.com/join?gc=327405&source=liveDashboard. The group that gains the top spot in the quizizz game will win the game. 1. The momentum of an object depends upon the object's ___________&_____________. a. size and shape b. mass and speed c. mass and velocity d. mass and energy 2. When the velocity of an object is doubled, its momentum a. remains unchanged in accordance with the conservation of momentum. b. doubles c. quadruples d. decreases 3. Which object listed below has the greatest momentum? a. A 0.05 kg object rolling at 0.2 m/s b. A 0.15 kg object rolling at 2 m/s c. A 0.15 kg object rolling at 1 m/s d. A 0.4 kg object rolling at 2 m/s 4. What causes change in momentum? a. force b. impulse c. time d. energy 5. An egg is thrown to a wall and a bed. What is the explanation why the egg didn’t break when thrown at a bed? a. the impact of the force lessens because of the increased in time interval due to cushioning effect. b. the impact of the force lessens because the bed has smaller force c. the impact of the force lessens because the egg has shells d. the impact of the force lessens because the bed is thick Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” 7 V. ASSIGNMENT: Word Problem: Two ice skaters stand together. They “push off” and travel directly away from each other, the boy with a velocity of 1.50 m/s. if the boy weighs 735 N and the girl, 490 N, what is the girl’s velocity after they push off? (Consider the ice to be frictionless). Write your given and solution here. Re-write the computed masses in this table, Mass (kg) Velocity (m/s) Boy Girl Solution of girl’s velocity. Prepared by: Checked: Noted: JOEMARI V. ERESE Student-Teacher ERNESTO B. SUYU Master Teacher II MARIBEL G. SARAMBAO Head Teacher II Centro, Sto. Tomas, Isabela 3327 300606@deped.gov.ph “STNHS: Tahanan ng Karunungan” 8
