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Comment: Post Wrong and 100+ years Out of Date (Score 2, Insightful) 70

I think you're missing the point

Actually he has a very good point. The article is wrong: there is just as much mass "beneath your feet" since technically the entire planet is beneath your feet. The point is that the mass is, on average, located further from your feet near a mountain because of the thick crust which floats on, and displaces, the far denser mantle. The gravitational field depends not just on the mass but on the distance as well.

What I don't understand is how this counts as 'news'. The effect was discovered by the British Trigonometric Survey of India where they noticed a discrepancy in their measurements caused by the fact that the 'vertical' was not the same near the Himalayas. This was well over 100 years ago...hardly news.

Comment: Re:North Pole (Score 5, Informative) 467

by Roger W Moore (#49740205) Attached to: The Brainteaser Elon Musk Asks New SpaceX Engineers

The north pole and a circle of lat 1 + 1 / (2 * PI) north of the south pole.

Actually the answer is the north pole and a circles of lat 1 + 1 / (2*pi*n) north of the south pole where n=1,2,3,4... etc. plus there is a slight correction because the surface of the earth is not entirely flat and so the circumference of a line of latitude is actually less than 2*pi*s where s is the arc length from the line to the south pole for the distances involved it would probably be negligible compared to surface defects.

Comment: Re:Texting Maths (Score 1) 384

And ironically, math is the most useless subject we learn and should be severely curtailed in high school.

Really? So you clearly have never built anything (especially in the US where you use all those fractions of an inch). I'd also watch our for those government tax collectors if you did not use any maths to fill in your tax return....and that's before we even mention finances with interest rates etc.

I strongly suspect that you use maths a whole lot more than you realize...unless you really are a genuine troll and live in a cave.

Comment: Pressure Matters but probably not Much (Score 1) 803

by Roger W Moore (#49739235) Attached to: Oregon Testing Pay-Per-Mile Driving Fee To Replace Gas Tax

Assuming a reasonable pressure (no trains with flanged wheels trying to drive down the highway) then the damage comes from axle load and not pressure for standard road building materials.

Yes but the strength of materials is usually measured by elastic modulus which has the same dimensions as pressure. Hence, although a bike will elastically deform a small area of the surface with the pressure it applies, it will deform it more than a car with lower pressure tyres. However I doubt this is where the damage comes from but rather from the motion of the vehicle. The dynamic load of a car travelling at speed will be many, many times greater than a cyclist who is less massive and slower moving. Similarly for lorry it will be many times larger still than a car. We would need an engineer to confirm but I expect that this is where the damage comes from since the dynamic load can be many times larger than the static one.

Comment: Non-residents (Score 1) 803

by Roger W Moore (#49739151) Attached to: Oregon Testing Pay-Per-Mile Driving Fee To Replace Gas Tax
In addition it will be interesting to hear how they plan to tax non-residents, including those of us from Canada. The nice thing with taxing petrol is that you are likely to fill up somewhere in Oregon if you are driving through. There is no extra delay and most people passing through will end up paying no matter where they live. With a mileage tax system are they going to stop you at the border and take a reading and a second when you leave? If not then suddenly non-residents will be paying nothing unfairly increasing the burden on those who live there.

Comment: Texting Maths (Score 5, Insightful) 384

Actually, ironically, one of the best reasons to use pen and paper is for maths. It's rather hard to express matrices, vectors, integrals etc. in a text message. You need LaTeX and a graphical display and its a lot slower than pen and paper. An equation editor is even slower.

Comment: Re:One Daft Question (Score 1) 64

In other words, we see further into the past by much more than a single year for every elapsed year

No, the universe was opaque until the plasma cooled and released what is now the CMB. We cannot see further back in time with light. Hence the only reason we can see further into the past each year is because that event (the universe becoming transparent) is getting further away from the present. Currently the amount of that event we can see is increasing - a trend which will eventually reverse due to dark energy - but it all occurred ~380k years after the Big Bang. So the only way we see further back is to let the present get further away or use something other than light like neutrinos.

Comment: One Daft Question (Score 1) 64

Does it mean that, as time goes on, we're going to be able to see farther back in time and space?

Obviously the answer is yes because, as time goes on, the period at which the CMB was emitted moves further into the past so obviously we are seeing "further back in time" but only at the rate of one year further per year past (on average). Since the universe is also expanding we are also looking further. This is about as insightful as pointing out that as time goes by I can remember events further back in time.

Comment: The other side of the coin (Score 1) 211

by Roger W Moore (#49691249) Attached to: FCC May Stop 911 Access For NSI Phones

Easy to say until you or someone you know and love are the person being denied access to 911 because of this rule change.

The question you also need to ask is how many people are dying because of the delays caused by responding to fraudulent emergency calls? I also fail to see how anyone is being 'denied' access to emergency calls: this is a choice they make when they purchase the mobile. If they choose to purchase a communication device without 911 access this is no different from those of us who make the choice not to own a mobile at all. I would hardly say that I have been denied access to 911 simply because I choose not to own a mobile and, if it were true, isn't that my choice to make?

Comment: Re:Standardized Testing (Score 1) 284

by Roger W Moore (#49684281) Attached to: Bill Gates Still Trying To Buy Some Common Core Testing Love

Standardized testing has been implemented in all East Asian countries for decades. You could check the result of our education systems. They're complete failures...

Standardized testing has been used in the UK since at least the 1950's and yet I would argue that it has been a great success there although there has been a problem of dropping standards in the past 10-20 years. As someone who has taught students from Asia the problem, as I see it, is far more to do with the style of education - rote learning - than with standardized testing. This does not prepare people well for science at the university level where you have to be curious, ask questions and think around problems. You cannot succeed by memorizing facts.

Comment: Re:Standardized Testing (Score 1) 284

by Roger W Moore (#49684195) Attached to: Bill Gates Still Trying To Buy Some Common Core Testing Love

Standardized testing is quite recent. Think of any great idea, any great civilization, any great thinker; none is steeped in standardized testing.

Standardized testing arose about the same times as public, compulsory education. The problem it addresses is the need for measuring students against a fixed, known standard. Before there were schools everywhere the reputation of the educational establishment or individual was used to judge the standard because there were few enough institutes/people that you could know the standards of a good fraction of institutes.

Today you are likely unaware the reputation and standards of schools beyond the boundaries of your local town and probably not even all of them if you live in a city. What standardized testing provides is a fixed, known standard that you can know and be aware of regardless of where a student went to school. Without a known standard - however you achieve it - grades are worthless as a certification of knowledge.

Comment: Standardized Testing (Score 4, Insightful) 284

by Roger W Moore (#49681291) Attached to: Bill Gates Still Trying To Buy Some Common Core Testing Love
Thinking about standardized testing reminds me of the Churchill quote: "Democracy is the worst form of government except for all the others.". Standardized testing has its problems but these are no where near as significant as the problems with everything else which has been tried.

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