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Insert succinct description of demonstration. A PASCO cart attached to a mass with a string running over a smart pulley is accelerated at a constant rate. A computer together with the PASCO interface can be used to measure the position, speed, and acceleration as a function of time.(Similar to 1G10.25)
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||apparatus||ME, Bay B1, Shelf #2|| ||
||all other parts||ME, Bay B1, Shelf #2|| ||
||...||ME, Bay B1, Shelf #2|| ||
||PASCO Track||ME, Bay B1, Shelf #2|| ||
||PASCO Cart||ME, Bay B1, Shelf #2|| ||
||PASCO Smart Pulley w/Photogate||ME, Bay B1, Shelf #2|| ||
||String||ME, Bay B1, Shelf #2|| ||
||Weight||ME, Bay A1, Shelf #2|| ||
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 * ''''' '''''  * '''''If using the PASCO interface is desired for the graphical output, a 24-hour notice is required.'''''
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 1. List steps for setup then procedure.
 1. ...
 1. Place the PASCO track on the lecture bench.
 1. Using the height adjustment screws on the track, level the track.
 1. Place the PASCO cart on the track, and add weight to it if desired.
 1. Attach the PASCO smart pulley and photogate to the track.
 1. Use the Velcro to keep the cart in place while the weight is attached and the string run over the pully.
 1. When ready, give the cart a push in the desired direction of travel, and observe it accelerating at a uniform rate.

 Optional Addition of the PASCO Interface with Computer:
 1. Boot the computer, and attach then power on the PASCO interface.
 1. Open Data Studio which is accessible from the desktop.
 1. Open the experimental setup file which is located in //
 1. Follow the above steps omitting the final step where the cart is released.
 1. When ready to release the cart, click on "start run" in Data Studio to begin taking data.
 1. Release car.
 1. Just before the cart collides with the bumper, stop the run by clicking "end run" in Data Studio (see plot below for an example).

attachment:TestRun2-400.jpg
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 *  * N/A
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Discuss the physics behind the demonstration, explaining some of the various steps of the demonstration when appropriate. The net force acting on the cart is a little less than the weight pulling it down the track. There is also some friction in the axles of the car and in the pulley which acts to oppose the motion of the cart. The magnitude and direction of these forces remains constant throughout the demonstration. Therefore, by Newton's second law, since F = m*a = constant and since m is constant so must the acceleration remain constant. Because of this constant acceleration, we expect the position vs. time curve to be quadratic in time, and we also expect the velocity vs. time curve to be linear in time.

[:PiraScheme#Mechanics: Table of Mechanics Demonstration]

[:MEEquipmentList: List of Mechanics Equipment & Supplies]

[:Demonstrations:Lecture Demonstrations]

Constant Acceleration Car, 1G10.10

Topic and Concept:

Location:

  • Cabinet: [:MechanicsCabinet:Mechanic (ME)]

  • Bay: [:MechanicsCabinetBayA1:(A1)]

  • Shelf: #1,2,3.. attachment: mainPhoto

Abstract:

A PASCO cart attached to a mass with a string running over a smart pulley is accelerated at a constant rate. A computer together with the PASCO interface can be used to measure the position, speed, and acceleration as a function of time.(Similar to 1G10.25)

Equipment

Location

ID Number

PASCO Track

ME, Bay B1, Shelf #2

PASCO Cart

ME, Bay B1, Shelf #2

PASCO Smart Pulley w/Photogate

ME, Bay B1, Shelf #2

String

ME, Bay B1, Shelf #2

Weight

ME, Bay A1, Shelf #2

Important Setup Notes:

  • If using the PASCO interface is desired for the graphical output, a 24-hour notice is required.

Setup and Procedure:

  1. Place the PASCO track on the lecture bench.
  2. Using the height adjustment screws on the track, level the track.
  3. Place the PASCO cart on the track, and add weight to it if desired.
  4. Attach the PASCO smart pulley and photogate to the track.
  5. Use the Velcro to keep the cart in place while the weight is attached and the string run over the pully.
  6. When ready, give the cart a push in the desired direction of travel, and observe it accelerating at a uniform rate. Optional Addition of the PASCO Interface with Computer:
  7. Boot the computer, and attach then power on the PASCO interface.
  8. Open Data Studio which is accessible from the desktop.
  9. Open the experimental setup file which is located in //
  10. Follow the above steps omitting the final step where the cart is released.
  11. When ready to release the cart, click on "start run" in Data Studio to begin taking data.
  12. Release car.
  13. Just before the cart collides with the bumper, stop the run by clicking "end run" in Data Studio (see plot below for an example).

attachment:TestRun2-400.jpg

Cautions, Warnings, or Safety Concerns:

  • N/A

Discussion:

The net force acting on the cart is a little less than the weight pulling it down the track. There is also some friction in the axles of the car and in the pulley which acts to oppose the motion of the cart. The magnitude and direction of these forces remains constant throughout the demonstration. Therefore, by Newton's second law, since F = m*a = constant and since m is constant so must the acceleration remain constant. Because of this constant acceleration, we expect the position vs. time curve to be quadratic in time, and we also expect the velocity vs. time curve to be linear in time.

attachment: photo

attachment: photo

attachment: photo

attachment: photo

Videos:

References:

  • List any references

[:Instructional:Home]

fw: Constant_Acceleration_Car (last edited 2018-07-18 16:41:02 by srnarf)