Excellent Albert–thanks for those. 🙂
Phil

A few things about your method are not ideal. It is probably too late to change this now, but at least you can make amends in your evaluation.I’m not sure why you are using a wheeled truck and an air track. You usually use a “v-shaped” unwheeled metal “vehicle” which is then pretty frictionless. Or use a wheeled truck on a long(wooden or metal) runway which you friction-compensate by tilting the runway until the vehicle when given a gentle momentary push then moves down the runway at a steady speed(Newton’s first law).
The way you are measuring the KE gain and GPE lost is not ideal as you are only measuring the average KE gain for a given GPE lost. This should give you a lower figure for the KE rather than the higher one quoted.
It may have been better to have measured the GPE lost from the fallen height to striking the floor(75cm say) and then to have measured the speed gained over a distance of 10-20 cm electronically AFTER the falling mass has hit the floor.( electronic timing should mean that you can measure over a shorter distance and still retain accuracy) The truck is then moving at a steady speed(no forces on it) and will be the final KE reached.
Your KE gained should ALWAYS be less than the GPE lost in such experiments due to energy losses — air resistance with moving objects, friction in the pulley and possibly some friction due to poor friction-compensation being the most obviouse areas.
I hope this long answer is of some use to you.

Phil

Hi William, I don’t have the exact date on the slide, but you are correct about ’69. On those long days spotting at Speke, the old Fox Moth was often the only thing to move all day bouncing across the grass
If you have more photos of Speke in those days I would love to see them.

Phil

I was also a member of the MGAE/MSAE for a while in the early 60’s.It’s great to see pictures from this period. I hope this isn’t the start of a scouse clique :p
Phil

It was my first time there Adrian. We were down that way for a family wedding, so a good chance to see aeroplanes. 😀
It’s a great place for a day out with its fantastic large(free!!) viewing area and lots going on all day. You can also get some great shots(Minolta Z2)
Phil

Here are e few more taken just after the fire was extinguished. In the “old days” I remember engines being started with portable extinguishers on a trolley nearby. The fire engines had to move through the many people still at the show to reach the fire.
Phil

Here are a few late pictures from Tuesday’s photoshoot and fast taxi.It was also nice to put a couple of faces to names(Darren and Damien).
Phil

A couple taken at Interlarken last year.

Phil 🙂