Name: Palma, Joebert Jr. A. Date: 14 January 2016 Cooperating Teacher: Mr. Joey Kevin D. Tiongco A Detailed Lesson Plan in Physics for Grade 9 8:20 AM – 9:10 AM I.
Objectives: At the end of the lesson, the students should be able to: a) identify the types of collision b) describe the effects of momentum in collision c) derive equations using momentum formulas for collision; and d) cite the importance of collisions in everyday life
II. Subject Matter: “Collisions” III. Instructional Materials A. Audio Visual Aids: PowerPoint/Prezi Presentation B. References 1. Padua, A. & Crisostomo, R. (2010). Practical and explorational physics: modular approach. Quezon: Vibal Publishing House, Inc. 2. Nave, C. (2016). HyperPhysics: mechanics. Georgia State University. Retrieved, 9 January 2016, from http://hyperphysics.phy-astr.gsu.edu/hbase/elacol.html 3. The Physics Classroom (2015). Mechanics: momentum and collisions. Retrieved 9 January 2016, from http://www.physicsclassroom.com/calcpad/momentum IV. Procedure Teacher’s Activity
Students’ Activity
A. Routine 1. Greetings Good morning, class. How’s —Good morning, Sir. your day? Who’s absent today?
—We’re fine, Sir. Thank you. —Nobody is absent, Sir.
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B. Motivation Today, we will have an activity. Here, I have several cards and each card has a statement. Since you are in three columns here, we will have three groups for this activity. With these cards, I will ask you to sort them into what are true statements and what are false statements. Later, I will ask those who are seated at the back of your column to present your cards. You have 3 minutes, class, to discuss.
Okay, Sir.
True/False Cards C1
A basketball will bounce back higher than its height of release.
C2
A bowling bowl will bounce on beach sand.
C3
When you push a wall, the wall pushes you back.
C4
It’s possible that Neptune can collide with Pluto.
C5
There is collision in playing chess.
C6
In theory, a planet collided with Earth which brought the extinction of dinosaurs.
C7
When you dribble a basket ball at an angle, the ball will bounce in the same angle. 2
Are you ready now to present, class? Let’s start with Group 3. Presenters, please come here in front and present your cards. Very good, Group 3. You are correct that cards 3, 5, abd 7 are true while the others are false. [The activity ends when all questions are answered.] C. Presentation of the Lesson Now, what do you think will our topic be about? Yes, Jane? Very good, Jane. Surely our topic is about collision, can anybody tell me something about collisions? Yes Wynn? That’s correct, Wynn. Collisions happen when objects bump or clashes on surfaces or on other objects, but more practically, can anybody give me an example of a collision? Yes Carl? Very good, Carl. Car accidents brought about by collisions are very dangerous, so when in a moving vehicle, be
Yes, Sir. Sir, the True statements are: Cards 3, 5, and 7. The others are false.
About objects that collide, sir? Sir, I think, collisions happen when objects clash into each other or into surfaces.
During a car crash, or even when a basketball hits the ground when being dribbled.
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mindful of the safety precautions like wearing seatbelts or protective wear. Understood?
Yes sir.
Later on, we will be discussing different categories of collisions, which will explain the difference between the collisions between objects. Are you ready? A. Activity Very well. Now, I will group you into 5. Since we’ve checked about your familiarity with collisions, per group I will give you sets of marbles that you will manipulate depending on the instructions that I will be giving. Are you grouped and ready class?
Yes sir!
We are grouped and ready sir.
Be ready, because after this activity, I will have you explain what we have done with the marbles. Okay class, here is the first instruction, I need you to make two marbles collide with each other. Done?
[The students do so, and make observations] Yes, sir.
Next, put one marble at rest and have one marble collide with it. Are my instructions
Yes, sir. [The students do the as what is instructed and made 4
clear so far class? Have you done it? Lastly, have one of your members hold one marble in place using a finger, done? Now make the other marble collide with the one that is being held in place. B. Analysis Now that we’re done, sit tight and let’s start explaining what had happened with your activity, ready class? On the first task, you made the two marbles move towards each other so that they will collide. After colliding, what happened to the marbles? Yes, Andy? You’re correct, Andy. In the first instruction, the two marbles moved apart after colliding. How about the second task? Who can give us observations about what had happened when a marble in motion, collided one marble that was at rest? Yes Tristan?
observations]
Yes, sir.
[The students do so and made observations]
Yes sir!
Sir, the two marbles instantly moved apart from each other, in opposite directions.
Sir, when the moving marble collided with the one at rest, the non-moving marble moved along the direction of the moving marble.
Correct, Tristan. In the case of the second task, when the moving marble collided with 5
the one at rest, the two marbles moved in the same direction. How about the third task? The marble in motion collided with the one that was being held down, what observations have you taken about this event? Yes Andrea? You’re right, Andrea. In the third instruction, the moving marble, obviously, bounced back as it collided with the held marble. C. Abstraction Class, go back to your seats now. Here, I have a tennis ball. Observe what happens when I drop the ball on the floor. [drops ball] Class, what objects collided when I dropped the ball? Yes, Jan? Correct, Jan. The ball and the floor collided. Now, what type of collision happened? May I ask Jet? Very good, Jet. When the ball
Sir, the moving bounced back.
marble
The ball and the floor collided, Sir.
Elastic collision, Sir.
bounced, elastic collision happened. In the activity earlier, which one was elastic 6
collision? Yes, Ann? Very good. The first instruction was an example of elastic collision. Now, eyes here in front. I will drop a plastic container on the floor. I want you to observe and identify what type of collision will happen. [drops a plastic container] Can you identify what type of collision happened? May I ask, Jena? You’re right, Jena. Inelastic collision happened when I dropped the plastic bottle on the floor. Why do you think it is inelastic collision? Yes, Miles? Very good, Miles. The plastic bottle did not reach its original position after bouncing. In scientific terms, some of the bottles kinetic energy was lost. Now, I will drop a book on the floor. What do you think will happen, class? Will the book bounce? Yes, Leah? Thank you, Leah. You’re right.
The elastic collision was the first instruction, Sir. The two marbles bounced and moved separately.
Inelastic collision happened, Sir.
After colliding, Sir, the plastic bottle did not reach its original position when it bounced.
The book will not bounce, Sir.
Let’s see what will happen when I drop this book. [drops book] 7
Leah is right, class, that the book will not bounce. Now, what type of collision is this? May I ask Carl? Why is it perfectly inelastic, Carl? Very good, Carl. Since the book did not bounce, its kinetic energy was lost in the collision with the floor. So class, what are the three types of collision? Yes, Mark? Very good, Mark. The types of collision are elastic, inelastic, and perfectly inelastic. Now, class, from your activity, what factors have great effects in the collision of marbles? Yes, Allysa? Very good, Allysa. Mass and velocity can affect collision. And we call that momentum. What do you think will happen, class, if I will roll this marble to a bowling bowl? May I ask Vince? Why will it bounce to the other direction? Very, good. Therefore, mass and velocity momentum. In my
can
affect
Perfectly inelastic, Sir.
It is perfectly inelastic, Sir, because the book did not bounce at all or all of its kinetic energy was lost.
The three types of collision are elastic, inelastic, and perfectly inelastic.
From the previous lesson, Sir, I think mass and velocity affects the collision of marbles.
The marble will bounce to the opposite direction, Sir.
The marble will bounce to the other direction, Sir, because the bowling is heavier than the marble.
PowerPoint 8
presentation, I will show you how collision works with momentum. Class, momentum is mass in motion. Therefore, we can assume that heavier objects have greater momentum. However, light objects can also have as much momentum as a heavy object, depending on its velocity. Momentum p = mv m1v1 + m2v2 = m1v1’ + m2v2’ Again class, describe the effects of momentum in collisions. May I ask Jana? Very good, Jana. So in physics or in mechanics, momentum is very useful because it has practical applications. So later, you will discover why they are important in the practical world. For now, class, I want you to derive formulas. Last week, you spent time on deriving formulas from a given
Momentum can determine how strong the impact will be in colliding objects, sir. Heavy objects and fast objects can have great momentum, and therefore, can alter objects after collisions.
equation. So now, you will apply what you have learned. With your learning buddy, I 9
want you to find the value of v1 and v2, and m1 and m2 in the equation m1v1 + m2v2 = m1v1’ + m2v2’. I will only give you 3 minutes. Are you now ready, class? [sample computation] May I ask Karylle to find the value of v1, on the board please. Thank you, Karylle. Now, using the derived formulas, I will give you a sample problem. D. Application Class, please work with your pair in answering this sample problem. A 0.01-kg marble was rolled to the right at 0.05 m/s and made an elastic collision with a 0.015-kg marble moving to the left at 0.03 m/s. After the collision, the smaller marble moved to the left at 0.002 m/s. Find the velocity of the 15-g marble after collision.
[student answer] Given:
Find: Solution:
I will only give you 5 minutes to do this.
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Are you done, class? May I ask Angelie to show their answers on the board? So, after collision, the velocity of the larger marble is 0.002 m/s, which is equal to the velocity after collision of the smaller marble. As you noticed, the two marbles have different mass and velocities but they have equal velocities after collision. What can you infer, class? We discussed it earlier. Can I ask, Jena? Very good, Jena. Collision and momentum will depend on the mass and velocity of objects. D. Values Integration So, class, is collision important in our life? May I ask Karl? Karl, what do you think is the importance of collision or the mere understanding of collision?
Heavier objects can have great momentum, sir. However, light objects can also have great momentum if they are moving fast.
Through understanding, collisions, sir, we can prevent casualties in road accidents.
Very good, Karl. So through understanding how collision works, we can reduce 11
casualties in road accidents. Another hand please. Yes, Jerome? You’re right, Jerome. Again, as you have sad, the mass and velocity of an object have effects on its impact. So class, that is all for today. Thank you for your participation. Good bye and thank you, class.
We can prevent damages in materials, sir, especially those which are fragile, when we understand collision.
Good bye and thank you, Sir Jb.
V. Assignment A. What: Solve the given problem: A 1800-kg car is moving at 30 m/s eastward. It collides head on with a 2200-kg garbage truck. What is the initial velocity of the truck if the car and the truck move together after collision at 12 m/s? B. Where to write: One whole intermediate paper C. When to pass: Next meeting D. Number of points: Thirty (20) points VI. Strategies Used Motivation Lesson Proper a) Group discussion b) Lecturette c) Values integration
True/False Cards Group discussions and “colliding marbles” activity; Presentation (definition of momentum, types of collisions, and momentum formulas); Q&A
Application
Paper and pen, learning buddy
Assignment
Written assignment.
Subject Matter Expert for EDUC 910: Ms. Mary June Gonzales 12