2 Table of Contents Pages Introduction Minds on projectile motion Beauty of projectile motion Activity 1 Activity 2 Inquiry Activity 1 Inquiry Activity 2 Inquiry Activity 3 Ponder Activity 1 Ponder Activity 2 Reference 1 2 5 9 10 11 15 19 23 24 26
1 INTRODUCTION Inquiry learning began in 1996 as found in the National Science Education Standards. The inquiry learning model is about understanding and applying scientific concepts and methods in science learning (Bell, Urhahne, Schanze, and Ploetzner, 2010). Inquiry is a student approach in teaching and learning to build their own knowledge and understanding through investigation and exploration based on existing knowledge. Malaysia Education Development Plan (PPPM) 2013 - 2025 emphasizes inquiry skills as learning skills. Smartphone is used as communication and mobile device. However, in 21st century smartphone is integrated as online learning device such as Google Classroom and Google Meet It also has a technology built-in such as accelerator, light sensor, magnetic sensor, temperature, gyroscope, camera with video, microphone and Global Positioning System. Computer is known as a machine that receives data as input, processes and manipulate data using programs and processed data as information outputs. Programs in term of simulation software in computers are used as predictor the future of the system or hypothetical situation. Computers can be connected together to form networks, allowing connected computers to interact with each other. In this Projectile Motion Inquiry Learning (ProMIL) activities, students have chances to explore the functions of smartphone and hands-on inquiry activities anywhere at any time. There is no limitation Thus, teaching and learning through smartphone can help students experience and enjoy gaining new knowledge. In a conclusion, students could be motivated and engaged through science learning.
2 Figure 1 : Projectile motion sy = H = maximum height, vy = 0 m s-1 sx = R = maximum distance = range, sy = 0 m Projectile motion is any object that once projected or dropped continues in motion by its own inertia and is influenced only by the downward force of gravity. In addition, projectile motion is a motion that involves the resultant of two motions which is the vertical motion (free fall) and the horizontal motion (linear motion). Smart Tips https://qrgo.page.link/PYYVU MINDS ON PROJECTILE MOTION 43
3 Table 1 : Component of projectile motion Linear Motion Projectile Motion x – component (horizontal) y – component (vertical) = 0 = = − = v = u + at = + = = constant = + = − v u 2as 2 2 = + x x x x x x v u v u a s = = + 2 2 2 y y y y y y y v u gs v u a s 2 2 2 2 2 2 = − = + 2 2 1 s = ut + at s u t s u t a t x x x x x = = + 2 2 1 = = 2 2 1 2 2 1 s u t gt s u t a t y y y y y = − = + s (u v)t 2 1 = + s u t s u v t x x x x x = = ( + ) 2 1 s u v t y y y ( ) 2 1 = + Velocities at point B : = = = − Magnitude at point B : = √() + () Direction at point B : = − ( )
4 Students are suggested to use ustva table to solve projectile motion problems. Fill in the given ustva table as shown in Table 2 for any given information in projectile motion problems. Table 2 : ustva table Horizontal − + Vertical + − t = = = − = . −
5 https://qrgo.page.link/8HdJs State an application regarding to this case. Calculate the velocity of the ball as it reaches the ground. 2 = 2 − 2 2 = 7 2 − 2(9.81)(−8) = −14.35 m s −1 Figure 2 Figure 3 https://qrgo.page.link/hAbBh State an application regarding to this case. Calculate the velocity of the coconut as it reaches the ground. 2 = 2 − 2 2 = 0 − 2(9.81)(−150) = −54.25 m s −1 BEAUTY OF PROJECTILE MOTION Case 1 ( = 90) Case 2 ( = 90) A. FREE FALL MOTION 0 m s −1 150 m 8 m 7 m s-1 P 30 minutes
6 https://qrgo.page.link/wrzGY State an application regarding to this case. List down the components of initial velocity. = = = 4.5 m s −1 = 0 m s −1 https://qrgo.page.link/cjjWH State an application regarding to this case. List down the components of initial velocity. = = 6 65 = 2.54 m s −1 = = 6 65 = 5.44 m s −1 Figure 4 Figure 5 Case 2 ( = 0 ) B. PROJECTILE MOTION Case 1 ( ) 65 u = 6 m s-1 10 m u = 4.5 m s-1 2.2 m h
7 https://qrgo.page.link/NZqnQ State an application regarding to this case. List down the components of initial velocity. = = 3 60 = 1.5 m s −1 = = 3 60 = 2.6 m s −1 Figure 6 Figure 7 Case 3 () sy u = 4 m s-1 70 sx Case 4 () https://qrgo.page.link/x8fWh State an application regarding to this case. List down the components of initial velocity. = = 4 70 = 1.37 m s −1 = = 4 70 = 3.76 m s −1 60 1.5 m sx u = 3 m s-1
8 https://qrgo.page.link/uhS8p State an application regarding to this case. List down the components of initial velocity. = = 15 35 = 12.29 m s −1 = = 15 35 = 8.60 m s −1 Figure 8 Free fall motion Case 1: v = -54.25 m s-1 Case 2: v = -14.35 m s-1 Projectile motion Case 1: ux = 2.54 m s-1 , uy = 5.44 m s-1 Case 2: ux = 4.5 m s-1 , uy = 0 m s-1 Case 3: ux = 1.5 m s-1 , uy = 2.6 m s-1 Case 4: ux = 1.37 m s-1 , uy = 3.76 m s-1 Case 5: ux = 12.29 m s-1 , uy = 8.60 m s-1 sy u = 15 m s-1 35 sx Case 5 ()
9 Exploring the functions of smartphone device Objective To explore the built-in sensors in your smartphone Apparatus / material • A smartphone device (Model Oppo A ) • “Phyphox” free application from Google Play Store is installed Procedures 1. Install the “Phyphox” app into your smartphone. 2. Open the “Phyphox” app. 3. List out the built-in sensors, the range and its units. 4. Click ○i symbol on the top right of the “Phyphox”and click Device info. 5. Scroll down to get built-in sensors, range and unit. Findings 1. List out the built-in sensors in your smartphone and the range: No Built-in Sensors Range Unit 1 Accelerometer 39.2266 m s-2 2 Magnetometer 4912.0 µT 3 Rotation Vector 1.0 Nil 4 Gyroscope 34.905556 rad s-2 5 Ambient Light 65535.0 lx 6 Proximity 5.0 cm 7 Linear Acceleration 156.99008 m s-2 8 Attitude 1.0 Nil 2. List out the other useful apps that you have installed using built-in sensors of your smartphone: Sensor Box for Android, All-In-One Toolbox, Sensor Tool Box, Sensors Test. ACTIVITY 1 phyphox.org 30 minutes
10 Design a simple science experiment using smartphone Objective To design a simple science experiment using your own paper A4. Task Design a simple science experiment in your group by using smartphones, built in sensors and free application. Objective: To investigate the light intensity versus distance. Experimental Design (List the experiment procedures and your experimental setup): Suggested experiment using “Phyphox” app: 1. Scroll down Raw Sensors feature, select Light. 2. Open and place the torch light to the light sensor in smartphone. 3. Repeat step 3 and 4 by moving the torch light from the smartphone in 5 cm increments for four readings. 4. Do intensities vary as distances change? Findings: Distance (0.1 cm) Light intensity, (0.000001 Lux) 5.0 16124.216527 10.0 1052.437621 15.0 534.876548 20.0 295.674321 25.0 178.334256 ACTIVITY 2 https://qrgo.page.link/tZp 2V 30 minutes
11 Exploring a projectile motion simulation using computer Objective To conduct an inquiry activity based on projectile motion. Inquiry Questions ▪ What is the initial velocity of the object? ▪ What is the height of the falling object? ▪ What is the range of the projected object? The activity is to explore the kinematics linear motion in everyday life. There are a few applications of free fall motion which are throwing ball upwards and releasing an object from a certain height. Basic theory A. An object at rest experiencing free fall motion from a certain height h above the ground. Therefore, the object depends on initial velocity, u and acceleration of gravity, g. Its height, h is ℎ = 2 2 B. A body is projected with an initial velocity, u and makes an angle, to the horizontal. The body has a range, R with time, t. The equation range, R is given by = 2 2 Hypothesis A. The higher the height of the object the faster the initial velocity of the fallen object. B. The larger the range of the object the faster the initial velocity and the larger the initial angle. Material • A computer per group with “PhET Interactive Simulations” (“PhET Interactive Simulations” is a free 3D virtual created by PhET Colorado Boulder University team, 2000) Variables The variable to be changed (independent variable) is A. Initial velocity B. Initial velocity & initial angle INQUIRY ACTIVITY 1 https://qrgo.page.link/afYPh 60 minutes
12 The variable to be monitored (dependent variable) is A. Maximum height B. Range The variable(s) to be kept constant (controlled variable(s)) A. Initial angle B. Height List the activities procedure Suggested simulation: Part A: 1. Click https://phet.colorado.edu/en/simulation/projectile-motion 2. Select Lab. 3. Change the angle, = 900 and height, h = 0 m. 4. Play the “PhET Interactive Simulations” and determine the maximum height. 5. Calculate the maximum height by using free fall motion. 6. Is there any difference for maximum height between simulation and calculation? Part B: 1. Then, change the angle and height, h = 0 m. 2. Use equation = 2 2 to determine R. 3. Change the distance, R. 4. Do you get the target? What is the value of distance? 5. Now, change the object. 6. Is there any difference between the distances, R for both objects?
13 Findings Part A: Calculation value : 2 = 2 − 2 0 = 122 − 2(9.81) = 7.33 m Simulation value : = 7 m Part B: Calculation value : = 2 sin 2 = (18) 2 sin(2 75) 9.81 = 16.5 Simulation value : = 16.5
14 Conclusion A. The higher the height of the object the faster the initial velocity of the fallen object. = 7 m B. The larger the range of the object the faster the initial velocity and the larger the initial angle. = 16.5
15 Exploring a free fall motion experiment using smartphone Objective To conduct an inquiry activity based on free fall motion. Inquiry Questions ▪ What is the initial velocity of the load? ▪ What is the height of the falling load? The activity is to explore the kinematics linear motion in everyday life. There are a few applications of free fall motion which are throwing ball upwards and releasing an object from a certain height. Basic theory An object at rest experiencing free fall motion from a certain height h above the ground. Therefore, the object depends on time, t and acceleration of gravity, g. Its height, h is ℎ = 1 2 2 Hypothesis The higher the height of the load the longer the time of the fallen load. Apparatus/material • A smartphone per group with acoustic installed (“Phyphox” is a free application software created by RWTH Aachen University, 2019) • Push Pen • DIY adjustable stand • Marble / Load • Meter rule Variables The variable to be changed (independent variable) is Height of the load. The variable to be monitored (dependent variable) is Time taken for the load to fall from a height. The variable(s) to be kept constant (controlled variable(s)) Mass of the load. INQUIRY ACTIVITY 2 https://qrgo.page.link/afYPh 60 minutes
16 List the experimental or activities procedure (Suggested experiment) 1. Scroll down to Timers feature, select Acoustic Stopwatch. 2. Open Acoustic Stopwatch. 3. Select and watch Video 2. 4. Conduct the first experiment. 5. Key in the threshold to 0.5 a.u. 6. Adjust the height h of the load to the point of impact. 7. Press the push pen that hang the load to make a sound or use other apparatus to make a loud sound. 8. Simultaneously play the acoustic stopwatch. 9. Record the value of h and t. 10. Repeat steps 2 and 3 for at least four different values of h. 11. Plot a graph of h against t 2 . 12. Determine the value of g from the gradient of the graph Figure 9 table DIY adjustable stand marble / load h push pen container
17 Result (Data and Analysis- Use “Excel” to plot graph) Gradient of the graph: = 2 − 1 2 − 1 = 499.4 cm s −2 Using equation comparing with straight line equation, ℎ = 1 2 2 = + Reading Height, h (±0.1 cm) Time, t (±0.001 s) t 2 (s2 ) t 1 t 2 tave 1 45.0 0.295 0.297 0.296 0.088 2 40.0 0.283 0.279 0.281 0.079 3 35.0 0.262 0.263 0.263 0.069 4 30.0 0.243 0.242 0.243 0.059 5 25.0 0.218 0.219 0.219 0.048 y = 499.4x + 0.7411 0 5 10 15 20 25 30 35 40 45 50 0 0.02 0.04 0.06 0.08 0.1 Height, h (±0.01 m)
18 Then, Gravitational acceleration: 1 2 =m = 2 = 2(499.4)=998.8 cm s-2 = 9.99 m s-2 % error = |9.81−9.99| 9.81 = 1.83% Discussion Conclusion Gravitational acceleration obtained from the experiment is g = 9.99 m s-2 which slightly differ from standard value, g = 9.81 m s-2 . The percentage error is 1.83%. This is because some errors occur when doing the experiment. The reaction time of the observer while pressing the push pen for release the load varies each time experiment is repeated. Error / Problem: 1. Failed to start or stop the acoustic stopwatch simultaneously when the push pen is pushed or load is landing on the container. 2. Sound from push pen could be detected by the acoustic stopwatch. 3. Length of push pen is measured incorrectly. Solutions / Precaution: 1. Release the push pen and make sure it is pushed simultaneously before start taking time. 2. Stay focus when start and stop the time so that sound can be detected by the acoustic stopwatch. 3. Length of push pen is measured from the push pen to the container. The hypothesis state that the higher the height of the load the longer the time of the fallen load is accepted. The value of acceleration of gravity is 9.99 m s-2 . The gravitational acceleration, g = 9.93 m s-2 .
19 Design a projectile motion experiment using smartphone Objective To conduct an inquiry activity based on projectile motion. Inquiry Questions ▪ What is the initial angle of the marble? ▪ What is the horizontal distance of the marble? The activity is to explore the kinematics linear motion in everyday life. There are a few applications of projectile motion which are a golf ball in flight, kicking a ball and shooting. This inquiry activity is to explore the application of projectile motion. Basic theory A body is projected with an initial velocity, u and makes an angle, to the horizontal. The body has a range, R with time, t. The equation range, R is given by = , = = 2 2 , = 2 2 Hypothesis The larger the initial angle of the marble the longer the flight time of the fallen marble. Apparatus/material • A smartphone per group with acoustic installed (“Phyphox” is a free application software created by RWTH Aachen University, 2019) • Push Pen • Straw • DIY wedge • Marble • Protractor installed (“Android Smart Protractor” is a free application software) • Track • Carbon paper / Double sided tape • A4 paper INQUIRY ACTIVITY 3 https://qrgo.page.link/t5FUX 60 minutes
20 Variables The variable to be changed (independent variable) is Initial angle The variable to be monitored (dependent variable) is Time of flight The variable(s) to be kept constant (controlled variable(s)) Mass of the marble List the experimental or activities procedure Suggested experiment: 1. Scroll down to Timers feature, select Acoustic Stopwatch. 2. Open Acoustic Stopwatch. 3. Click https://qrgo.page.link/t5FUX or scan QR code as suggested experiment. 4. Select an initial angle, . 5. Record the time, t in Acoustic Stopwatch. 6. Measure the range, R. 7. Calculate the acceleration of gravity, g and compare with true value. table carbon paper & A4 paper /double sided tape R DIY wedge marble Straw push pen track smartphone Figure 10
21 Result (Data and Analysis) Reading 1 When = 22 R= 0.61 m, = . = = = 0.61 0.224 = 2.723 m s −1 = = = 2.723 cos 22° = 2.937 m s −1 = 2 sin 2 = 2 2 = 2.9372 × 2(22°) 0.61 = . − Reading 2 When = 44 R= 0.45 m, = . = , = = = 0.45 0.292 = 1.541 m s −1 = = = 1.541 cos 44° = 2.142 m s −1 = 2 2 = 2 2 = 2.1422 × 2(44°) 0.45 = . −
22 Discussion Conclusion Gravitational acceleration obtained from the experiment = 22 is g = . m s-2 and = 44 is g = . m s-2 which slightly differ from standard value, g = 9.81 m s-2 . This is because some errors occur when doing the experiment. The reaction time of the observer while pressing the push pen for release the load varies each time experiment is repeated. Error / Problem: 1. Failed to start or stop the acoustic stopwatch simultaneously when the push pen is pushed or load is landing on the carbon paper. 2. Sound from push pen could be detected by the acoustic stopwatch. 3. Angle of push pen is measured incorrectly. Solutions / Precaution: 1. Release the push pen and make sure it is pushed simultaneously before start taking time. 2. Stay focus when start and stop the time so that sound can be detected by the acoustic stopwatch. 3. Angle of push pen is measured from the push pen to the carbon paper. The hypothesis state that the larger the initial angle of the marble the longer the flight time of the fallen marble is accepted. Gravitational acceleration, = 22 is g = 9.82 m s-2 and = 44 is g = 10.91 m s-2 .
23 TAKE A BREAK…… PONDER ACTIVITY 1 1. Lily threw a ball vertically upwards with an initial velocity of 15 m s-1 . Calculate the a. time for the ball to reach the maximum height. ( = 1.53 ) b. maximum height that can be reached by the ball. ( = 11.47 ) https://youtu.be/UMQVIpBnoeM Solution : a. maximum height, = 0 m s −1 = − 0 = 15 − 9.81 = . b. maximum height, = 0 m s −1 2 = 2 − 2 0 = (15) 2 − 2(9.81) = . 2. Siew Lee released a tennis ball from a cliff of 20 m height. Calculate the a. time taken for the tennis ball to reach the bottom of the cliff. ( = 2.02 ) b. velocity of the tennis ball just before it touches the ground. ( = −19.82 −1 ) https://youtu.be/BOOiR4B5Eoc Solution : a. = 0 m s −1 , = −20 m = − 1 2 2 −20 = 0 − 1 2 (9.81) 2 = . b. = − = 0 − (9.81)(2.02) = −. − Direction : downward 60 minutes
24 PONDER ACTIVITY 2 1. A squash ball is thrown upward by a player from the top of a building with velocity 12 m s-1 at an angle 20 to the horizontal. The height of the building is 45 m. Calculate the a. maximum height of the ball from the ground. ( = 45.86 ) b. magnitude of the velocity of the ball just before it strikes the ground. ( = 32.05 −1 ) https://youtu.be/rR8GQGwlQgw Solution : = 12 m s −1 , = −45 m a. = 0 m s −1 2 = 2 − 2 0 = (12 20) 2 − 2(9.81)ℎ ℎ = 0.859 m Maximum height from the ground, = 45 + 0.859 = . b. = = 12 20 = 11.28 m s −1 2 = 2 − 2 2 = (1220) 2 − 2(9.81)(−45) = 29.996 m s −1 Magnitude, = √ 2 + 2 = √(11.28) 2 + (29.996) 2 = . −
25 2. A cannon ball is fired with a velocity of 100 ms-1 at an angle of 35° above the horizontal. Determine the a. maximum height reached by the cannon ball. ( = 167.69 ) b. time of flight of the cannon ball. ( = 11.69 ) c. horizontal range of the cannon ball. ( = 957.64 ) d. velocity of the cannon ball just before it hits the ground. ( = 99.98 −1 , = 34.98° ) https://youtu.be/Gip8F_SaiBw Solution : = 100 35° = 81.92 m s −1 , = 100 35° = 57.36 m s −1 a. 2 = 2 − 2 0 = (12 20) 2 − 2(9.81) = . b. = 0 m = − 1 2 2 0 = 57.36 − 1 2 (9.81) 2 (57.36 − 4.905) = 0 = 0 s , = . c. = = 81.92(11.69) = . d. = = 81.92 m s −1 = − = 57.36 − (9.81)(11.69) = −57.32 m s −1 Magnitude, = √ 2 + 2 = √(81.92) 2 + (−57.32) 2 = . − = −1 ( ) = −1 ( 57.32 81.92) = . ° below the ground or below positive x-axis
26 REFERENCE Cutnell, J.D., Johnson, K. W., Young, D., & Stadler, S. (2015). Introduction to Physics (10th ed.). Hoboken, N.J: John Wiley & Sons. Kementerian Pendidikan Malaysia (2016). Panduan Pelaksanaan Pengajaran dan Pembelajaran Berasaskan Inkuiri. Bahagian Pembangunan Kurikulum. Putrajaya: Kementerian Pendidikan Malaysia. Kementerian Pendidikan Malaysia. (2018). Curriculum Specification. Bahagian Matrikulasi. Putrajaya: Kementerian Pendidikan Malaysia. PhET University of Colorado Boulder (2020). PhET Interactive Simulations. [Simulation software]. Retrieved from https://phet.colorado.edu/en/simulation/projectile-motion RWTH Aachen University (2019). Phyphox (version 1.1.3). [Mobile application software]. Retrieved from https://play.google.com/store/apps/details?id=de.rwth_aachen.phyphox Serway, R. A. & Jewett, J.a. (2014). Physics for Scientists and Engineers (9th ed.). International Student Edition. USA: Brooks/Cole Cengage Learning.
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