Year 12s: what will be the first way you research your future options? >>

A Physics Coursework Question

OK, so I'm doing Salters Horners AS Physics, coursework-y bit.

We're investigating how the speed of a wave changes with respect to the depth of the water. We carried out ten experiments by dropping a tray of water from a constant height, and measuring the time it took the wave to travel three lengths of the tray, 3 times. Divided it by 3 and hey presto, found the velocity.

Great, no problem.

Then, Dr Teacher wanted us to calculate Errors in our results, due to imperfect equipment, which is where the problems begin.

Error in depth was fine, we found percentage error in the depths and then mulitplied the original figure by this percentage, which was easy enough.

Error in velocity is the one I don't understand. I get the fact that Velocity = Distance / Time, and thus one should calculate errors in both and then add them together, but I just don't understand how to do this. Perhaps it is a mental block? I feel like I'm being thick.

Error in distance, I suppose, is a constant figure, as we used the same tray for the entire experiment. Error in Time, I guess is just the time measured + reaction time? Even if it is, I don't know how to calculate it...

Any ideas on how to do this? I've got about a week to do it, and I'm worrying, because I have better things to do than this...

Many thanks :smile: