Can u pls mention the shape of the sensor used..some info on the exact type of sensor used would also be helpful..

Sure. The shape of the collision sensor was circular, with the corresponding area.

Here is the link to the type of sensor: http://www2.vernier.com/booklets/dfs.pdf

Just to understand you right: You let this sensor bounce into a 'immovable' wall and wenn it get's repelled the Energy that is given is the lost energy means the difference between the energy bevor and after the collision?

And have you varied the Area A in your experiments oder only the Force that is applied?

That sounds right. With the equipment we borrowed, we obtained two force sensor head of difference area, yes. One was a metal (and rigid) screw in piece with a circular head (0.28 cm^2. Almost like a screw, but without the lines to insert a screw driver. The other was a rubber tipped (and compressible) screw in piece with a larger circular head (0.94 cm^2).

The rigid metal sensor head gave us data points which was very tight around the line. The compressible head was a little more difficult to work with, but had broader range and was not so tight around the line. I shall attach two pictures of the data next.

This is the metal data versus the line.

This is the rubber one.

Oh and the height of course comes from the standard E=mgh on the slanted ramp.

If you calculate the energy like this you get the total energy of the vehicle not the lost energy or do I see something wrong in your experimental setup?