Robin Hood's Profile
Scholar
167
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Smoke Signal
0

  • Scholar Asked on October 4, 2018 in ENVIRONMENTAL SCIENCE.

    The probability for such an event is practically zero in the next few billion years. If the Earth stopped spinning suddenly, the atmosphere would still be in motion with the Earth’s original 1100 mile per hour rotation speed at the equator. All of the land masses would be scoured clean of anything not attached to bedrock. This means rocks, topsoil, trees, buildings, your pet dog, and so on, would be swept away into the atmosphere.

    If the process happened gradually over billions of years, the situation would be very different, and it is this possibility which is the most likely as the constant torquing of the Sun and Moon upon the Earth finally reaches it’s conclusion. If the rotation period slowed to 1 rotation every 365 days a condition called ‘sun synchronous’, every spot in the Earth would have permanent daytime or nighttime all year long. This is similar to the situation on the Moon where for 2 weeks the front-side is illuminated by the Sun, and for 2 weeks the back side is illuminated. This situation for the Earth is not the condition of ‘stopped’ rotation, but it is as close as the laws of physics will let the Earth get.

     
    If it stopped spinning completely…not even once every 365 days, you would get 1/2 year daylight and 1/2 year nightime. During daytime for 6 months, the surface temperature would depend on your latitude, being far hotter that it is now at the equator than at the poles where the light rays are more slanted and heating efficiency is lower. This long-term temperature gradient would alter the atmospheric wind circulation pattern so that the air would move from the equator to the poles rather than in wind systems parallel to the equator like they are now. The yearly change in the Sun’s position in the sky would now be just its seasonal motion up and down the sky towards the south due to the orbit of the Earth and its axial tilt. As you moved along constant lines of Earth latitude, you would see the elevation of the Sun increase or decrease in the sky just as we now see the elevation of the Sun change from a single point on the Earth due to the Earth’s daily rotation.

    For example, if you were at a latitude of +24 degrees North in the Summer and at a longitude where the Sun was exactly overhead, it would slide gradually to the horizon as Fall approached, but since the Sun has moved 90 degrees in its orbit, it would now be due west. Then as we approach Winter, you would now be located on the dark side of the Earth, and would have to travel in longitude to a location 180 degrees around the Earth to see the Sun 1/2 way up the sky because in the Winter, the Sun is 48 degrees south of its summer location in the sky. It’s a little confusing, but if you use a globe of the Earth and orient it the right way, you can see how all this works out.

    As for other effects, presumably the magnetic field of the Earth is generated by a dynamo effect that involves its rotation. If the Earth stopped rotating, it’s magnetic field would no longer be regenerated and it would decay away to some low, residual value due to the very small component which is ‘fossilized’ in its iron-rich rocks. There would be no more ‘northern lights’ and the Van Allen radiation belts would probably vanish, as would our protection from cosmic rays and other high-energy particles. This is a significant biohazard.

    • 114 views
    • 1 answers
    • 0 votes
  • Scholar Asked on September 24, 2018 in PHILOSOPHICAL EDUCATION.

    Contemporary analytic philosophers of mind generally use the term “belief” to refer to the attitude we have, roughly, whenever we take something to be the case or regard it as true. To believe something, in this sense, needn’t involve actively reflecting on it: Of the vast number of things ordinary adults believe, only a few can be at the fore of the mind at any single time. Nor does the term “belief”, in standard philosophical usage, imply any uncertainty or any extended reflection about the matter in question (as it sometimes does in ordinary English usage). Many of the things we believe, in the relevant sense, are quite mundane: that we have heads, that it’s the 21st century, that a coffee mug is on the desk. Forming beliefs is thus one of the most basic and important features of the mind, and the concept of belief plays a crucial role in both philosophy of mind and epistemology.

    From this perspective the “belief” part of “justified true belief” is what is characterized as “true” and “justified” since we may have beliefs that are neither true nor justified.

    It is not something that we, in addition, have to believe in. We already believe the fact but our belief might be incorrect. Now the question is whether that fact, that belief, actually is true and justified.

    • 86 views
    • 4 answers
    • 5 votes
  • Scholar Asked on July 20, 2018 in INFORMATION TECHNOLOGY.

    Case 1: You are connecting to open WiFi like somewhat you get in airports/public locations: There is no guarantee for any security on this case and that’s why most of the people not recommending to use Open WiFi network. Please refer: https://www.makeuseof.com/tag/3-dangers-logging-public-wi-fi/

    Case 2: Trusted network/SSID with authentication and WPA2: Much better security in terms of secured and authenticated wifi network with WPA2. How to ensure you are connected to WPA2 enabled WiFi network with a pre-shared key:

    Check your connected WiFi/Wireless network properties to ensure you are connected to WPA2 enabled network.

    • 205 views
    • 1 answers
    • 2 votes
  • Scholar Asked on July 20, 2018 in GEOGRAPHY.

    I was about to ask a question whether this should be classified as a sinkhole or not. This is because this so-called ‘sinkhole’ is not entirely because of a natural process. It seems that it was the underground GPO Station (or the tunnel) of Orange Line Metro Train Station that collapsed.

    I can’t seem to find an article that specifically mentions this. One news article I found isn’t exactly very clear about it, but suggests this to be the case.

    I think you can blame the ‘sinkhole’ (or collapse) or the failure of the underground structure. One of your source’s title “Those responsible for Lahore sinkhole will be punished” also seems to suggest that it has only man-made causes, and not natural.

    • 155 views
    • 1 answers
    • 3 votes
  • By using a non-compressible fluid, it acts like a solid push rod.

    • 217 views
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  • Scholar Asked on April 19, 2018 in PHYSICS.

    work done in rolling a stone is less than in lifting it

    • 193 views
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  • Pseudomonas

    • 216 views
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  • Scholar Asked on April 19, 2018 in PHYSICS.

    collision between fast neutrons and nitrogen nuclei present in the atmosphere

    • 189 views
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    • 0 votes
  • Knurling is a machining process normally carried our on a centre lathe. The act of Knurling creates a raised criss-cross pattern on a smooth round bar that could be used as a handle or something that requires extra grip.

    • 280 views
    • 1 answers
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  • lower pair

    • 240 views
    • 1 answers
    • 0 votes