Basic Idea:

• Measure the acceleration of a cart on an inclined track.

• 7 

	What:	How Many:	Where:
	Vernier Dynamics Tracks (see Vernier hardware photos below!)	1	non-Majors storeroom, on top of the shelves
	Vernier Cart without plungers	1	non-Majors storeroom, shelf E5
	Vernier Cart mass (rectangular) - 500 g Only need 4 mass blocks at most!	1 for ½ the tracks; see Notes	non-Majors storeroom, shelf E5
	Vernier Screw and wingnut (attaches mass to cart)	1 for each cart mass	non-Majors storeroom, shelf E5
	Vernier Cart Picket Fence (used as cart flag)	1	non-Majors storeroom, shelf E5
	Vernier Track Bumper	1	non-Majors storeroom, shelf E5
	Soft foam padding (cushions track bumper)	1	non-Majors storeroom, shelf E5
	Pasco Photogate bracket (not the Vernier bracket!) (attaches photogate head to track!)	1	non-Majors storeroom, shelf F4
	Pasco short photogate mounting screw (attaches photogate head to bracket! See photo below)	1	non-Majors storeroom, shelf BB4 (in small plastic bag in box with accessory photogates)
	Pasco Photogate timer and power brick 3rd generation ONLY! Preferred over 4th/5th/6th generation photogates!! See Notes.	1	non-Majors storeroom, shelf BB4 or 151 Lab
	Knife edge clamp	1	non-Majors storeroom, shelf C2
	0.5-m Meterstick	1	non-Majors Storeroom, shelf AA4
	30 m measuring tape	1	non-Majors storeroom, shelf AA4
The following may already be in the lab if this experiment follows the Free Fall experiement
	Small bench clamp Black clamps only; the gray ones don't hold tight!	1	non-Majors storeroom, shelf C4
	Short Steel Rod (10 mm x 25 cm)	1	non-Majors storeroom, shelf A3

Notes:

• Lab Setup (photo details):
• Notes:
  • The tracks are labeled (A through H). Arrange them as shown in the figure below.
  • The carts on tracks B, D, F & G will get a 500-g mass added ("Heavy"); tracks A, C, E & G do not require additional mass ("Light")
    • Put the head of the mass attachment screw into the center slot of the cart. Align the rectangular mass so that it's axis is parallel to the cart, and use the wing-nut to attach the mass near the center of the cart (see photo details page)
  • Important Photogate Notes!
    • Take the 3^rd generation photogate timers from the air tracks in the University Physics lab Phys151 Conservation of Momentum. Use only 3^rd generation photogates (marked on back 3A, 3B, etc.) NOT 4^th/5^th generation (4A, 4B, …, 5A, 5B, …)
    • Remove the photogate head from the timer support rod by unscrewing the photogate mounting screw (2.0 cm long) from the plastic rod clamp. Put the plastic clamp and the screw in a safe location in the lab. The photogate head is attached to the photogate bracket using the short photogate mounting screw (1.5 cm long). The two screws and rod clamp are shown in the photo at right (click for a larger view)
    • Attach the photogate near the 110.0 cm mark; Jeff will fine tune position before lab. See photo details page.
  • Only use the black small bench clamps! The clamps that are gray do not hold the support rod without wiggling. See Figures 1 & 2 below for connection notes.
  • Stuff Jeff will do - Don't attach the knife edge clamp or the picket fence flag!
    • Set the height of the raised side of the track using an iPhone for calibration to 3°. The knife edge clamp is tightened after the height is adjusted.
    • iPhone calibration & angle adjustment (see photo details as well):
      • Use a bubble level to find the area of the sink that is acceptable to use (no, the sink isn't level!)
      • Calibrate a bubble level app on iPhone on this area of the sink. It works well by having the iPhone lay down on its back, lifting it on the short edge to measure the angle
      • Lay iPhone on track, with long axis of phone parallel to track length. Adjust track angle to 3.0°
      • Lift the downhill side of the iPhone, then lay it down again. The angle will generally change a small amount. Again adjust track angle to 3.0°
      • Repeat a few times until the angle always reads 3.0° after laying the iPhone down again
    • Attach the picket fence flag to each cart. It will be aligned in the grooves closest to the student

  

• Attach small bench clamp to table as shown in Figure 1 below. The track angle is very small, so the clamp cannot be inverted (as it is in the previous week's experiment, Figure 2):

 

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• Vernier Hardware (photos courtesy Vernier Software & Technology)
  Vernier Cart (w/plunger)
  Vernier Cart (w/o plunger)
  Vernier cart mass, screw & wingnut
  Vernier Cart Picket Fence
  Vernier Dynamics Track, adjusting legs & Adjustable End Stop