Measurement of the acceleration due to gravity using the graphic calculator

 

Apparatus

 

Picket fence, retort stand with clamp, photogate, data logger and graphic calculator with DATAGATE program installed.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


Arrangement

 

  1. Clamp the photogate rigidly to a retort stand so the arms extend horizontally, as shown above.  To avoid damaging the picket fence, make sure it has a soft landing surface.
  2. Connect the calculator to the data logger.
  3. Connect the photogate to DIG/SONIC port of the data logger.
  4. Turn calculator ON.
  5. Press .
  6. Select DATAGATE.
  7. Press .

8.      Select SETUP.

9.      Select MOTION.

10.  Select PICKET FENCE.

11.  Select OK.

12.  Select START.

 

Procedure

 

1.      Hold the top of the Picket Fence and drop it vertically through the photogate.

2.      Using the cursor  select VELOCITY and press .

3.      Examine the VELOCITY VS TIME graph  (Fig.1). 

·        Press  

·        Select RETURN TO MAIN SCREEN 

·        Select ANALYZE

·        Select CURVE FIT

·        Select LINEAR (VELOCITY VS TIME)

          The screen now shows the equation of the line   ( Fig.2)                                                                      

·        Record the slope

·        Press  to see the fitted line with the data

·        Press

·        Select RETURN TO ANALYZE SCREEN

·        Select RETURN TO MAIN SCREEN

4    Repeat procedure steps 1, 2 and 3 five more times to get average for g.

 

Sample Results

 
 

 
 

 

 

 

 

 

 

 

 

Fig. 2
 
 


                      Fig. 1

                                                                                         

The slope of the velocity versus time graph, i.e. A as given on the screen, is a measure of acceleration due to gravity.

In this case the value of g is found from the graph to be 9.79 m s-2.