Changes

==Acceleration on an inclined plane==

==Acceleration on an inclined plane==

The XO laptop can be used to do experiments on motion, rolling a ball down a ramp. The XO1.5 is faster and better suited for this. Inexpensive sensor switches can be made of aluminium foil. The switches are 5cm wide to provide an on time which is long enough to measure.

The XO laptop can be used to do experiments on motion, rolling a ball down a ramp. The XO1.5 is faster and better suited for this. Inexpensive sensor switches can be made of aluminium foil. The switches are 5cm wide to provide an 'on' time which is long enough to measure.

The logging rate can be increased (Turtle Blocks104) by patching one of the Turtle Art files, <i>talogo.py</i> in directory <i>home/olpc/Activities/TurtleArt.activity/TurtleArt</i> changing <i>self.max_samples</i> from 1500 to 150, This reduces the repeat loop from 15mS to 4mS but there is around 50mS jitter. Datalogging can be done without patching the file, using wide switches and shallow ramps keeps the events within the capability of the XO laptop.

The logging rate can be increased (Turtle Blocks104) by patching one of the Turtle Art files, <i>talogo.py</i> in directory <i>home/olpc/Activities/TurtleArt.activity/TurtleArt</i> changing <i>self.max_samples</i> from 1500 to 150, This reduces the repeat loop from 15mS to 4mS but there is around 50mS jitter. Datalogging can be done without patching the file, using wide switches and shallow ramps keeping the events within the capability of the XO laptop.