Set up a picket fence timer

Use this timer to measure position, speed, and acceleration of a cart that has a picket fence attached. Also measure the acceleration due to gravity when dropping the picket fence through a photogate.

Equipment setup

• Photogate

  Use a Wireless Smart Gate (PS-3225), a Smart Gate (PS-2180) with a PASPORT interface, or a Photogate Head (ME-9498A) with a digital interface. Mount the photogate on a track if measuring the motion of a cart. Mount the photogate to a ring stand if measuring the acceleration due to gravity.

• Picket Fence

  Use either the Smart Timer Picket Fence (ME-8933) or Cart Picket Fence (ME-9804) if measuring the motion of a cart, as shown in the first image below. Use the Picket Fence (ME-9377A) if measuring the acceleration due to gravity, as shown in the second image below.

Set up the timer

1. Connect the photogate to SPARKvue.
2. Under Select measurements for templates, click the Properties icon next to the photogate's name, or next to the digital interface's name if using a Photogate Head.
3. Click One Photogate or Device or Smart Gate Only, select Photogate and Picket Fence, and click OK.

4. Enter the Flag Spacing. This value is equal to the distance between the leading edges of two flags. Click OK when finished.

   

5. Check the boxes next to the measurements you want to display.

6. Select a template to display the selected measurements.

Record data

Click Start , then let the entire picket fence pass through the photogate. The first time the photogate is blocked, it records a position of zero. The second time the photogate is blocked, it records the second position and the speed. The third time the photogate is blocked, it records a third position, a second speed measurement, and the acceleration.