# John Rennie

Chester, United Kingdom

ratsauce.co.uk

Age: 52

Semi retired old time computer nerd who started programming on a Commodore Pet.

Since I'm also active in the Physics forum I should add that I started as a theoretical chemist, moved into solid state photochemistry and finally worked in industry as a colloid scientist. I only became a full time computer nerd in 1997.

 31m reviewed Approve suggested edit on Question about the shape of the waves 31m reviewed Approve suggested edit on Why is a paramagnetic material attracted into a magnetic field? 31m reviewed Approve suggested edit on Which body will have a greater "Rotational" kinetic energy? A solid cylinder or a hollow cylinder. (SAME MASS) 31m reviewed No Action Needed UPS Status calculations 3h comment Question about the shape of the wavesI think you need to expand your question to clarify what you're asking. Sine waves generally occur when the potential energy of your system is quadratic i.e. $V(x) \propto x^2$. 4h reviewed Close What is the correct formula to use for finding the change in position for this spring (SHM) at time t? 18h revised Why were some of my flags declined?oops 18h reviewed Close Centrifugal force in inertial reference frame 18h reviewed Leave Closed What is the independent variable in the dual slit experiment? 20h comment Point masses and infinite densities@I'm-A-Crackpot-QUACK-CRANK: all physical theories are approximate models of reality that break down if pushed beyond their area of validity. So Newton's laws are an approximation that break down at speeds near $c$, special relativity is a better approximation but breaks down for high densities, general relativity is a still better approximation that breaks down when quantum effects become important and so on. The model of a point mass is a useful approximation because we expect quantum effects to become important only at lengths to small for us to measure. 23h answered Point masses and infinite densities 23h awarded Reviewer 23h reviewed Close Length of second pendulum is decreased by 1% then the gain or loss in time per day is:- 1d reviewed Approve suggested edit on Are cell phones that operate $5\: \mathrm{GHz}$ damaging? 1d reviewed Approve suggested edit on Does a second similar source of white noise increase the overall noise level? 1d comment Is light slower when traveling inside a gravity field?These seem to be about attempts to measure dispersion rather than the speed of light. 1d answered Is light slower when traveling inside a gravity field? 1d reviewed Leave Open Can we actually prove with 100% accuracy that there is more than 3 dimensions plus time (t,x,y,z)? 1d reviewed Close What is the independent variable in the dual slit experiment? 1d reviewed Close How does air escape from a pneumatic tire?