I need help with the second part at the bottom. Investigation B: Energy Loss Due to Air Resistance.
Posted: Sat Jul 09, 2022 12:00 pm
I need help with the second part at thebottom. Investigation B: Energy Loss Due to AirResistance.
Energy Part 2 Investigation A: Energy Loss in a Bouncing Ball Purpose: to observe the motion of a bouncing ball and to calculate the fractional energy loss in each bounce. Materials: a 2-meter stick, a ball, and a phone (for capturing a video of the bouncing ball) Introduction: In an idealized world free of dissipative forces, a ball dropped from rest would bounce forever, reaching the same maximum height after each bounce. In the real world, a ball will lose some fraction of its mechanical energy after each bounce, and the height it reaches will decrease with each bounce. To a pretty good approximation, a ball will lose the same fraction of its energy each time it bounces. This allows us to define a constant called the coefficient of restitution, which is equal to the ratio of the mechanical energy of the ball after a bounce to the mechanical energy of the ball before a bounce. We will denote this constant with the variable c. Of course, c depends on the material properties of the ball and the surface it is bouncing on, and will have different values for different combinations of bouncing object and surface. Procedure: 1) Prop a meter stick against a wall so it is completely upright. Tape the meter stick against the wall if necessary to hold it in place. 2) You will need to work as a team with your lab partners for this next part. One person in your group will be in responsible for dropping the ball and another person in your group will be responsible for capturing a video of the motion. Hold the ball next to the meter stick so that the underside of the ball is exactly at the 1.5 meter mark. Make sure the entire meter stick is in frame, and begin recording the video. Drop the ball and make sure to record at least 5 bounces on video. Number of Bounces Height Reached (m) Total Energy (J) 0 1.5 1.1 1 1.04 0.76 2 0.75 0.55 3 0.49 0.36 4 0.37 0.27 5 0.25 0.18 3) Use your video to determine the maximum height reached after 0, 1, 2, 3, 4, and 5 bounces. Use the underside of the ball as your reference point. Record your measurements in Table 1 on the previous page.
4) Measure the mass of your ball (in kg) using the triple beam balance and record the value below 0.075 kg m 5) Calculate the total energy (in Joules) of your ball after 0, 1, 2, 3, 4, and 5 bounces. When the ball reaches its maximum height, it will be momentarily at rest (because its direction of motion is reversing). At this moment, all of the energy will be in the form of potential energy (and none will be in the form of kinetic energy). This means you can use E = mgh to calculate the energy. Show your work for each calculation below and record your values in Table 1 on the previous page. E Number of bounces: 0 => Total energy = mgh = (0.075) (9.8) (1.5) = 1.1 J Number of bounces: 1 => Total energy = mgh = (0.075) (9.8) (1.04) = 0.76 J Number of bounces: 2 => Total energy = mgh = (0.075) (9.8) (0.75) = 0.55 J Number of bounces: 3 => Total energy = mgh = (0.075) (9.8) (0.49) = 0.36 J Number of bounces: 4 => Total energy = mgh (0.075) (9.8)(0.37) = 0.27 J Number of bounces: 15-> Total energy = mgh = (0.075) (9.8)(0.25) = 0.18 J = 6) Make a plot of maximum height reached vs. number of bounces (hN vs. N) in excel. Insert an exponential trend line to fit to your data. Display the equation for your best-fit trend line. Print out this plot and include it in your lab report. Copy down your best-fit exponential trend line equation below. Ask your instructor for help if you have trouble using excel. E₁/Eo 0.69 E₂/E₁ 0.72 E₂/E₂ 0.65 E4/Es 0.76 Es/E4 0.68
7) For each bounce, calculate the ratio of the energy of the ball after and before the bounce. Use your energy values from Table 1 to make these calculations, and show your work in the space below. Record your results in Table 2 above. E1/EO=0.76/1.1 0.69 E2/E1 = 0.55/0.76= 0.72 E3/E2 = 0.36/0.55 = 0.65 E4/E3= 0.27/0.36 = 0.76 E5/E4 = 0.18/0.27 = 0.68 8) Calculate the average of your values in table 2 and show your work below. This number is called the coefficient of restitution, c c= (0.69 +0.72 -0.65 +0.76-0.68)/5 = 0.70 9) Repeat steps 1-8 for a different ball (your instructor will provide this). Record your data in the tables below and show your work in the blank space below. Number of Bounces E₁/Eo E₂/E₁ E₂/E₂ E4/E3 Es/E4 I choose m = 0.25 kg Height Reached 0 1 2 3 4 1.5 0.79 0.45 0.22 0.12 0.063 0.49 0.58 0.49 0.54 0.52 Total Energy (J) 3.7 1.9 1.1 0.54 0.29 0.15
10) Each time the ball hits the ground; some fraction of its mechanical energy is lost. The energy does not simply disappear! It is converted to other forms of energy. Where did the lost energy go (i.e., what forms of energy might it have been converted to)? The energy it might converted Investigation B: Energy Loss Due to Air Resistance Purpose: to observe the loss of mechanical energy of a falling object due to air resistance Materials: a sheet of paper and a motion detector Procedure: 1) Place your motion detector face up on your table and start up LoggerPro. Grab 10 sheets of paper from the scrap paper bin by the printer. Take one of the sheets of paper and hold it 50 centimeters above the detector. Hit the collect button to begin recording data. When you start to hear the clicks from your motion detector, let the paper go. Stop recording data after the paper lands on the motion detector. 2) Use your data to determine the speed of the paper just before it landed on the detector. Record your measurement below. V= m/s 3) Find the mass of your sheet of paper. To do this, place all 10 sheets on the triple beam balance and find their mass. Then divide by 10 to get the mass of a single sheet. Record your measurement below, in units of kg. m= kg 4) Calculate the initial mechanical energy (Ei) of your sheet of paper. Use the equation below and set the height to h = 0.50 meters, and the speed to v = 0. E = mgh+1/2 mv² E = J
5) Calculate the final mechanical energy (Ef) of your sheet of paper by setting the height to h = 0 and the speed to the value you measured in step 2. E = mgh+1/2 mv² E= J 6) How much energy was lost due to air resistance (Ei-Ef)? Where did the lost energy go (i.e., what forms of energy might it have been converted to)?
- I Need Help With The Second Part At The Bottom Investigation B Energy Loss Due To Air Resistance 1 (141.14 KiB) Viewed 53 times
- I Need Help With The Second Part At The Bottom Investigation B Energy Loss Due To Air Resistance 2 (66.74 KiB) Viewed 53 times
- I Need Help With The Second Part At The Bottom Investigation B Energy Loss Due To Air Resistance 3 (59.25 KiB) Viewed 53 times
- I Need Help With The Second Part At The Bottom Investigation B Energy Loss Due To Air Resistance 4 (67.17 KiB) Viewed 53 times
- I Need Help With The Second Part At The Bottom Investigation B Energy Loss Due To Air Resistance 5 (19.72 KiB) Viewed 53 times
4) Measure the mass of your ball (in kg) using the triple beam balance and record the value below 0.075 kg m 5) Calculate the total energy (in Joules) of your ball after 0, 1, 2, 3, 4, and 5 bounces. When the ball reaches its maximum height, it will be momentarily at rest (because its direction of motion is reversing). At this moment, all of the energy will be in the form of potential energy (and none will be in the form of kinetic energy). This means you can use E = mgh to calculate the energy. Show your work for each calculation below and record your values in Table 1 on the previous page. E Number of bounces: 0 => Total energy = mgh = (0.075) (9.8) (1.5) = 1.1 J Number of bounces: 1 => Total energy = mgh = (0.075) (9.8) (1.04) = 0.76 J Number of bounces: 2 => Total energy = mgh = (0.075) (9.8) (0.75) = 0.55 J Number of bounces: 3 => Total energy = mgh = (0.075) (9.8) (0.49) = 0.36 J Number of bounces: 4 => Total energy = mgh (0.075) (9.8)(0.37) = 0.27 J Number of bounces: 15-> Total energy = mgh = (0.075) (9.8)(0.25) = 0.18 J = 6) Make a plot of maximum height reached vs. number of bounces (hN vs. N) in excel. Insert an exponential trend line to fit to your data. Display the equation for your best-fit trend line. Print out this plot and include it in your lab report. Copy down your best-fit exponential trend line equation below. Ask your instructor for help if you have trouble using excel. E₁/Eo 0.69 E₂/E₁ 0.72 E₂/E₂ 0.65 E4/Es 0.76 Es/E4 0.68
7) For each bounce, calculate the ratio of the energy of the ball after and before the bounce. Use your energy values from Table 1 to make these calculations, and show your work in the space below. Record your results in Table 2 above. E1/EO=0.76/1.1 0.69 E2/E1 = 0.55/0.76= 0.72 E3/E2 = 0.36/0.55 = 0.65 E4/E3= 0.27/0.36 = 0.76 E5/E4 = 0.18/0.27 = 0.68 8) Calculate the average of your values in table 2 and show your work below. This number is called the coefficient of restitution, c c= (0.69 +0.72 -0.65 +0.76-0.68)/5 = 0.70 9) Repeat steps 1-8 for a different ball (your instructor will provide this). Record your data in the tables below and show your work in the blank space below. Number of Bounces E₁/Eo E₂/E₁ E₂/E₂ E4/E3 Es/E4 I choose m = 0.25 kg Height Reached 0 1 2 3 4 1.5 0.79 0.45 0.22 0.12 0.063 0.49 0.58 0.49 0.54 0.52 Total Energy (J) 3.7 1.9 1.1 0.54 0.29 0.15
10) Each time the ball hits the ground; some fraction of its mechanical energy is lost. The energy does not simply disappear! It is converted to other forms of energy. Where did the lost energy go (i.e., what forms of energy might it have been converted to)? The energy it might converted Investigation B: Energy Loss Due to Air Resistance Purpose: to observe the loss of mechanical energy of a falling object due to air resistance Materials: a sheet of paper and a motion detector Procedure: 1) Place your motion detector face up on your table and start up LoggerPro. Grab 10 sheets of paper from the scrap paper bin by the printer. Take one of the sheets of paper and hold it 50 centimeters above the detector. Hit the collect button to begin recording data. When you start to hear the clicks from your motion detector, let the paper go. Stop recording data after the paper lands on the motion detector. 2) Use your data to determine the speed of the paper just before it landed on the detector. Record your measurement below. V= m/s 3) Find the mass of your sheet of paper. To do this, place all 10 sheets on the triple beam balance and find their mass. Then divide by 10 to get the mass of a single sheet. Record your measurement below, in units of kg. m= kg 4) Calculate the initial mechanical energy (Ei) of your sheet of paper. Use the equation below and set the height to h = 0.50 meters, and the speed to v = 0. E = mgh+1/2 mv² E = J
5) Calculate the final mechanical energy (Ef) of your sheet of paper by setting the height to h = 0 and the speed to the value you measured in step 2. E = mgh+1/2 mv² E= J 6) How much energy was lost due to air resistance (Ei-Ef)? Where did the lost energy go (i.e., what forms of energy might it have been converted to)?