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To investigate the validity of Newton’s 2nd law of motion  ·  Vernier Logger Pro  ·  Motion Detector  ·  Vernier LabPro Interface  ·  Linear Air Track system  ·  Cart with a flag on top  ·  Pulley  ·  String  ·  <span style="font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Various masses <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">The set-up of the system will be shown in class and the data collection will be executed based upon the instructions below. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 1)  <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Using an electronic balance, find the mass of the cart and record it in Table I (given below) <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 2)   <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Connect the USB link of the interface to your laptop first and then launch the Logger Pro <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 3)  <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Check the motion detector to make sure that it is facing to the cart with a slight upward angle. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 4)   <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">One student should hold the cart and the other should attach a small mass (record this mass in table I) to the string that is going over the pulley on the other end of the track <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 5)  <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">While still holding the cart, turn on the vacuum so that air starts flowing out of the air track <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 6)   <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Click “Start” on Logger Pro and release the cart. Just before the cart hits the other end of the track, click “stop”. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 7)  <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Repeat steps 4) to 6) with 2 more different masses (hanging) <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> Table 1: Mass of the cart (including the flag) 190.6 g = 0.1906 kg  <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">(kg)  ||  <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">   <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">Acceleration (m/s2)  <span style="font-size: 11pt; font-family: 'Times New Roman','serif'; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">(= slope of v-t graph acquired by Logger Pro) || <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';"> <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">Force of gravity on the hanging mass <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">(N) <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">F=mg <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">  || || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.067 ||
 * __<span style="font-size: 14pt; line-height: 150%; font-family: 'Times New Roman','serif';">[|1.docx][|1.docx]Experiment – Newton’s Second Law __**
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt; mso-no-proof: yes;">By: Julia Smith, Ji Youn Kim, Sanjay Chatrani **
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt; mso-no-proof: yes;">O ****<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">BJECTIVE **<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">
 * <span style="font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">APPARATUS **
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">PROCEDURE **
 * __<span style="color: #080cb8; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">PART A __**
 * <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">Mass of hanging mass
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">2.9 g = 0.0029 kg || 0.1446 || 0.028 ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1545 ||^   ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1475 ||^   ||
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">4.9 g = 0.0049 kg || 0.2365 || 0.048 ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.2420 ||^   ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.2346 ||^   ||
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">6.8 g = 0.0068 kg || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.3352
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.3507 ||^   ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.3286 ||^   ||

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 1)  <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">In this part, the hanging mass is kept constant. You have to add masses on each side of the cart and record their values in a table <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 2)   <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">As done n Part A, record the motion of the cart (with masses) on Logger Pro <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 3)  <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Repeat the above steps two more times for different masses on the cart <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Mass of hanging mass (kg) = 6.8 g = 0.0068 <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> (kg) || <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';"> <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">Acceleration (m/s2)  <span style="font-size: 11pt; font-family: 'Times New Roman','serif'; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">(= slope of v-t graph acquired by Logger Pro)   || <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';"> <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">Force of gravity on the hanging mass <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">(N) <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">F=mg <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> ||
 * __<span style="color: #080cb8; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">PART B __**
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Mass of cart
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">190.6 g = 0.1906 kg || <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';"> 0.3352 || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> <span style="font-size: 11pt; line-height: 150%; font-family: 'Times New Roman','serif';">1.86788=1.9   ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.3507 ||^   ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.3286 ||^   ||
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">291.1 g = 0.2911 kg ||< <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.2144 ||= <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">2.85278=2.9 ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.2045 ||^   ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.2136 ||^   ||
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">391.1 g = 0.3911 kg || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1581 ||= <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">3.83278=3.8 ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1537 ||^   ||
 * ^  || <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1690 ||^   ||

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> ** <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 1. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Draw a schematic diagram of the system and label all the forces (ignore friction between cart and the air-track) <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 2. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Draw a free body diagram of the cart <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 3. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Draw a free-body diagram of the hanging mass <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 4. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Write the eqautions for the net force for both masses separately. Eliminate the tension force to find the theoretical acceleration of the system <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Net force of cart=Ft <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Net force of hanging object=Fg-Ft <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Ft is equal for both objects because the pulley is mass less and frictionless. Ft is equal to ma and Fg is equal to m2g. <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">m2=hanging mass (0.0068 kg) <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">m1=mass of cart (0.1906 kg) <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1906a=0.0068(9.8)-0.0068a <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1906a+0.0068a=0.067 <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">0.1974a=0.067 <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">a=0.067/0.1974
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">ANALYSIS
 * <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">m1a=m2g- m2a **
 * <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">a=0.3394 m/s/s **

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 5. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Test the precision of your data by determining the percentage difference for accelration using the equation: <span style="font-family: 'Times New Roman','serif';"> <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">  <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">  <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">  <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">  <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">  <span style="font-size: 12pt; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 10.0pt; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">  % difference = (maximum value - minimum value) /average * 100 <span style="color: red; font-family: 'Times New Roman','serif';"> <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Average acceleration: (0.3352+0.3507+0.3286)/3 = 0.3382 m/s/s

=0.3507-0.3286/0.3382 * 100 <span style="color: red; font-family: 'Times New Roman','serif';">=6.53% Therefore, the percentage difference is 6.53%.

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 6. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Test the accuracy of your results by determining the percentage error for acceleration % error = [(measured value - accepted value) / accepted value] *100% <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">=|0.3382-0.3394/0.3394| * 100 <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">=0.3536% <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Therefore, the percentage error is 0.3536%. This value tells us we were very accurate with our experiment.

<span style="font-family: 'Times New Roman','serif'; letter-spacing: -0.15pt; mso-ansi-language: EN-GB;"> <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 1. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Describe the relationship between the net force acting on an object and the acceleration of the object when the mass of the object is constant, with the support of your data.
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">DISCUSSION QUESTIONS **

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 2. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Describe the relationship between the mass of an object and its acceleration when the net force is constant, with the support of your data. <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">The data shows that if the net force is constant, the greater the mass of the object, the lower the acceleration will be. This is seen in Part B of the experiment when the cart was 0.1906 kg and the acceleration was approximately 0.3382 m/s/s. Then, when the mass of the cart was increased to 0.2911 kg, the acceleration was lowered to about 0.2108 m/s/s. Therefore, our data shows that the heavier the object, the lower the acceleration will be. This rule also agrees with Newton’s Second Law which says that acceleration is inversely proportional to the mass of an object.

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 3. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Discuss the precision and accuracy of your experiment, based upon your calculation in step #4 of the data analysis.

The precision and accuracy of the experiment are very good as the precision is 6.53% off the accepted value and the accuracy is 0.3536% off the accepted value.

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 4. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Provide some possible reasons for the difference between the theoretical value of acceleration and experimental value of acceleration of the cart <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> <span style="color: #ed1212; font-family: 'Times New Roman', Times, serif;"><span style="font-size: 12pt; line-height: 115%; font-family: 'Times New Roman','serif';"> Some possible reasons for the difference between the theoretical value of acceleration and the experimental value of acceleration are: 1. The mass might have been swinging and not motionless when the machine was turned on, hence inaccurate results were taken. 2. The cart might have been placed at different positions on the scale for each recording preventing the cart to reach its maximum acceleration. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 5. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Assume that there is a frictional force between the track and the cart and the coefficient of friction between the two is 0.015. If the mass of the cart (including the flag) is 95.2 g and the hanging mass is 12.5 g. Predict the rate of acceleration, based upon the given information. Make sure that free body diagrams are drawn and proper principles are applied and steps are provided.

<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> 6. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Given an example of an application of Newton’s First Law and Third Law of Motion with sufficient explanation. Newton’s 1st Law - **// "every body continues in its state of rest of or uniform motion in a straight line unless it is acted upon by an unbalanced force". //**   <span style="font-family: 'Times New Roman','serif';">Newton’s 1st Law is proven while driving a car. The force of the road on the locked wheels provides the unbalanced force to change the car's state of motion, yet there is no unbalanced force to change the passenger’s own state of motion. Thus, the passenger continues in motion, sliding along the seat in forward motion. A person in motion tends to stay in motion with the same speed and in the same direction unless acted upon by the unbalanced force of a seat belt. Seat belts are used to provide safety for passengers whose motion is governed by Newton's laws. The seat belt provides the unbalanced force which brings the passenger from a state of motion to a state of rest.

Newton’s 3rd Law - **// The law states that for every action force, there exists a reaction force that is equal in magnitude but opposite in direction and acts on the first body. //** <span style="font-family: 'Times New Roman','serif'; mso-ansi-language: EN-US;"> <span style="font-family: 'Times New Roman','serif'; mso-ansi-language: EN-US;">Newton’s Third Law is proven when kicking a soccer ball. When playing soccer without shoes, the reason you feel pain is because the same amount of force you exert on the ball is being exerted back on your foot and therefore the harder you kick the ball, the greater the force and the more pain you inflict upon yourself. Also, it can be noted that national soccer players sometimes “pull a muscle” when they kick at the soccer ball but miss. This is explained through Newton’s Third Law. The player exerts a force with their foot but there is no equilibrium force and therefore the player “pulls a muscle”. <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Write brief and concise statements to address the objective of this law. <span style="color: red; line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Newton’s Second Law says that if an unbalanced force acts on an object, the object will accelerate. Its acceleration will be in the same direction of the force and inversely proportional to the mass of the object. Our results agree with the law because when we placed an unbalanced force upon the cart, the cart accelerated in the same direction as the applied force. Also, as the lower the mass of the cart, the greater the acceleration was. In regards to the hanging mass, it also agreed with Newton’s Second Law. It accelerated downwards and the acceleration was directly proportional to the force of gravity. The force was downwards and so the greater the force (the mass of the hanging object), the greater the acceleration of the hanging mass. Therefore, the results of this lab helped to show that Newton’s Second Law of Motion is correct.
 * <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Conclusion: **

<span style="font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> **<span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Rubric for Newton’s 2nd Law lab ** <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;"> <span style="font-family: 'Garamond','serif'; mso-bidi-font-size: 12.0pt;"> <span style="font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">Total mark __/12 =__ ___% <span style="line-height: 150%; font-family: 'Times New Roman','serif'; mso-bidi-font-size: 12.0pt;">
 * **<span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">Category ** || **<span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">50-59% **
 * <span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">(Level 1) ** || **<span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">60-74% **
 * <span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">(Level 2) ** || **<span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">75-89% **
 * <span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">(Level 3) ** || **<span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">90-100% **
 * <span style="font-size: 10pt; color: black; font-family: 'Arial','sans-serif';">(Level 4) ** ||
 * <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> **Lab results** || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Most of the data are incorrectly collected. || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> Most of data are collected, but with either no repetition or many of them are incorrect.  || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Most data are collected correctly and enough trials are used.  || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Data are collected with the highest degree of accuracy and precision.   ||
 * <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">3 || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> ||
 * **<span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Data analysis ** || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">No required free body diagrams are drawn accurately and the application of Newton’s laws of motion is not shown and no assessment on accuracy and precision is done || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Some of the required free body diagrams are drawn and Newton’s laws of motion are used with some difficulties. Assessment on accuracy and precision is done with errors. || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Most of the required free body diagrams are drawn accurately and Newton’s laws of motion are used somewhat correctly to find the tension in the system. Accuracy and precision are assessed with some errors || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Required free body diagrams are drawn accurately and Newton’s laws of motion are used correctly to find the tension in the system. Accuracy and precision are assessed correctly ||
 * <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">4 ||  ||   ||   ||   ||
 * **<span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Discussion questions ** || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> Many of the discussion questions are not answered or answered incorrectly. || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Some of the discussion questions are answered correctly, but very little elaboration is done || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Most of the discussion questions are answered correctly, but not enough reasons are provided to support each answer || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">Discussion questions are answered thoroughly and accurately and reasons for each answer are provided with evidence from the lab  ||
 * <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;">5 || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> || <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;"> ||