Thursday, November 20, 2008

AA 507

What the church needs in these days of peril is an army of workers who, like Paul, have educated themselves for usefulness, who have deep experience in the things of God, and who are filled with earnestness and zeal. Sanctified, self-sacrificing men are needed; men who will not shun trial and responsibility; men who are brave and true; men in whose hearts Christ is formed "the hope of glory," and who with lips touched with holy fire will "preach the word." For want of such workers the cause of God languishes, and fatal errors, like deadly poison, taint the morals and blight the hopes of a large part of the human race.

As the faithful, toilworn standard-bearers are offering up their lives for the truth's sake, who will come forward to take their place? Will our young men accept the holy trust at the hands of their fathers? Are they preparing to fill the vacancies made by the death of the faithful? Will the apostle's charge be headed, the call to duty be heard, amidst the incitements to selfishness and ambition that allure the youth?

-EGW-

Sunday, November 16, 2008

Static vs. Kinetic Friction and Other Observations

Today I found myself thinking back to an experience I had in academy. I was part of the ski club and we were on our weekly trip to Greek Peak when we saw an SUV stuck in the snow by the side of the road. Between the road being dry and only slightly curved, as well as the angle of departure from the road my only explanation was that this individual had been wanting to try out their four wheel drive (of which they seemed quite proud) along the side of some farmers field. It was suggested that, with a van full of high school students, we could help get this person out so we stopped to help. Over and over again we would dig out behind the wheels and get ready to push the car back the way it had come towards the road at which point the driver would floor the accelerator thus spinning and sliding themselves perpendicular to the direction they wanted to move. Back in the present I watched as a tractor was trying to get out of the mud from which it was trying to rescue a skidsteer that was also stuck for similar reasons - the strategy seemed to be to select the lowest possible gear (in low range of course) and give it full throttle... once again with similar results - if one wanted to dig holes, I think a shovel would probably have been less frustrating.

I would like to point out that the coefficient of static friction between two surfaces is always greater and usually significantly greater than that of kinetic friction - in this case meaning that a spinning tire has very little traction. Second, that increasing the torque to your wheels, although wonderful for doing heavy work without working the engine or clutch as hard, in no way improves your traction - to the contrary it makes it more difficult to keep your wheels from 'breaking free'. There is a reason why even some cars with automatic transmissions have an option to start off in second gear rather than first to make slipping less likely on soft and/or icy surfaces. Thirdly, increasing the speed of your tires when you have no traction will not help build up momentum to get over/through some obstacle but rather digs you into a deeper hole - literally!