Speed

The latest topic for the Loose Bloggers’ Consortium and we welcome a new member: Gaelikaa…please visit her blog along with the usual suspects :The Loose Blogging consortium: Grannymar, Marianna , Conrad, Ashok ,Ramana and Maria

Now to try and get up to speed on this topic.

According to my mother I was blessed with two speeds of operation: Dead Slow and Stop….. but she was always comparing me unfavourably with my sister who was fast. Mm! I wonder if I should rephrase that?

Whilst pondering this subject I came across many quotations about speed including this one from some unknown American:

Scientists tell us that the fastest animal on earth, with a top speed of 120 feet per second, is a cow that has been dropped out of a helicopter.

I was forced to ponder why the cow was in the helicopter in the first place.

I realised that I was finding it difficult to be serious about the subject and so I thought to find out what serious people had to say. Here is the Mahatma Gandhi ;

There is more to life than simply increasing its speed.

And wouldn’t you just know it…up pops Woody Allen with:

I took a speed-reading course and read War and Peace in twenty minutes. It involves Russia.

Charles M Schultz, who gave us Peanuts, apparently said;

Life is like a ten-speed bike. Most of us have gears we never use.

How true…and my bike has 21 speeds. Where does that leave me, I wonder?

So what is speed? Of what does it consist?

The Online Dictionary gives us 8 definitions as a Noun, 5 as a transitive verb and 4 as an intransitive verb. That is just for a start.

I naturally tend towards the definition used in Physics, a science for which I have no aptitude at all:

The ratio of the distance travelled by an object (regardless of its direction) to the time required to travel that distance.

This is followed by the legend; Compare velocity.

This is interesting as it shows how limited the use of a Thesaurus can be from time to time. Many would say that speed and velocity are the same thing and, indeed, in terms of the units used to express them both quantitatively they are. So they are synonyms. However, or BUT if you wish, they are not the same qualitatively. Velocity is a vector and as such it has direction. Speed has no requirement of direction.

Little realisations such as this are important to understanding Physics it seems.

The speed of light….now there’s an interesting concept….we all know that it is constant don’t we? But is it? If it was constant then lenses and prisms would not work. These instruments work because the wave passing from one medium, say, air , into another, say, glass, changes speed….curious that. Then , on re-emerging the wave regains its original speed. Curiouser…. as Alice might have said…just think what Charles Dodshun might have had Alice do if he had known of Einstein’s work.. I digress.

As I understand it, the speed of light is a physical constant and is the speed at which electromagnetic radiation (visible light, radio waves, micro waves, x-rays etc etc etc..now we have the King of Siam in this!) travels in a perfect vacuum, or free space as a physicist might call it.

This constancy is interesting. It means that where ever you are and where ever you observe or measure  the speed of light it is always the same. (in a vacuum of course)

So, there you are sitting astride a photon ( photon; a particle of light…don’t ask) whizzing along with your camera at…you guessed it..the speed of light. You take a picture of a passing star and your flash gun fires. Off goes the light from your flash gun at the speed of light. Now, if you measured the speed of that light from aboard your photon it would be 299 792 458 m/s and if an observer on the star measured the speed of the same light it would be 299 792 458 m/s. This is counter intuitive. Just think of the situation if you were sitting aboard a car and you had a catapult. The car travels at 100km/hour and you fire your catapult projectile so that it travels away from the car and in the same direction at a speed of 100km/hr then an observer at the side of the road would measure the speed of the projectile at 200km/hr. Wouldn’t they?

Curiouser and curiouser….. now what about firing the catapult backwards…or the flashgun…Mmm! Must think about that…

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14 Responses to “Speed”

  1. Grannymar Says:

    Magpie, I think you enjoyed that! I know I did. I wish you were a teacher when I was at school…… Wait now that would not work, When I was five you were only six.

  2. magpie11 Says:

    Well, I remember having to play teachers the day after the coronation!

  3. gaelikaa Says:

    Very nice post, rather deep for me. But I love to challenge myself. I will reread this. The quotes you used were fantastic. Mahatma Gandhi pops up everywhere doesn’t he? We just celebrated his birthday here in India on 2nd October!

  4. magpie11 Says:

    I just sort of wandered around the topic….. typical of how my mind works.
    reference to Alice and Charles Dodshun was because Dodshun (pen name Lewis Carroll) was a mathematician..his ideas were weird enough without Einstein. The King of Siam reference was to Yul Bryner as same in The King and I ..at some point he says, imperiously, “Etcetera, etcetera, etcetera.”

    Ghandi might have been a thorn in the side of the Raj but he actually had some very astute ideas…I also celebrated his birthday..thanks to Google who had an image of him on their header.

    I am going to finish reading the other blogs tomorrow.

  5. Maria Says:

    Oh, I am glad you did not change the part about your “fast sister”. I never had a sister, but if I did, I would tease her unmercifully.

    I have heard of tipping a cow, but not from a helicopter. Since we have many flying over us on there way to the Navy Base, I will watch out for cow dropping pilots.

    I had this quote that I didn’t use, but love so I will leave it here in your comments. “Speed isn’t always an advantage… The snails were on board Noah’s Ark with the cheetahs”

  6. Marianna Says:

    For someone who is not a physics fanatic, you forged ahead and did a great job of fostering further thought on fast. (Ok, speed, but I wanted to continue with the alliteration!)

  7. Conrad Says:

    What a madman! You are treading on turf that I love. So, Mr. Magpie, my hand is raised in the corner.

    If I were traveling right on the photon, wouldn’t time dilation dictate that the time passage in the external world would have stopped?

    Sorry, teach, just being ornery, LOL. This post was fun.

  8. Ursula Says:

    Magpie, I used to go to sleep in physics lessons – not because of the laws of physics but because the teacher was maloderous and boring. We all felt sorry for him.

    One line which piqued where it hurts was your reference to bikes. I grew up when bikes were just bikes: You pedalled or, when the incline too steep, you pushed. Whenever I hit mainland Europe and its autobahns I put metal on the pedal of the car; but put me on a bike with GEARS and I retard. I do not understand the concept, neither do I wish to. I clearly have some sort of mental block there.

    By the way, nowadays, your mother would call you “laid back” which is one of the best positions in life to be in.

    U

  9. Rummuser Says:

    Magpie, this post, starting from your quip about your fast sister and all the comments on the post is a collector’s item. Besides the fast sister, let us go one by one: Playing Teacher? I have heard of playing Nurse, but teacher? Maria says “cow dropping pilots” – cow droppings perhaps is what she meant? And finally, Ursula says, “laid back” is one of the best positions in life to be in. For who? If you get the drift!

    Coming to the post itself, one of the reasons that I got drawn into philosophy is the little example a Guru gave about the myth of time. The sun is 8.4 light minutes away from earth and the nearest star to our earth is Proxima Centauri which is 4.2 light years away from us. In other words, if something went wrong with the sun, it will take us eight minutes and a few seconds here and there to die. The brightest star that we see at dusk is actually something that existed more than four years ago and may not even exist at the time that it is perceived! Time is a joke played on us by Creation or God or Natural Selection or whatever you want to call it.

    I may be stoking the wrath of Ursula and Conrad with my flippancy and let us hope that they will rise to the bait.

  10. Ursula Says:

    Ramana, rise to the bait? I always do, at the slightest provocation. Yet, I can’t see your worm for looking – so sweet a person you are. Tonight I am at my mellow best. Maybe Conrad will do better and be caught in your net.

    Time is indeed a big joke played on us, with its wilful dynamics, playing tricks on our minds; ‘waiting’ in particular being the devil’s own invention as to test one’s mettle.

    Yes, the sun: Let’s hope it won’t suddenly blow its fuse. Who can sort out their legacy, paperwork, board the cat and make a will in eight minutes flat?

    U

  11. magpie11 Says:

    Mmm! I just knew I’d get something wrong so I’m going to travel at 0.9 c…But i think i got the point across about the constancy…I await some simple instruction. I only started to begin to understand anything about Special relativity after reading “The Time and Space of Uncle Albert” by Russell Stannard to the kids at school. ( http://www.faber.co.uk/author/russell-stannard)… I love playing with concepts and encouraging children to think about unusual ideas… like “an Infinity of Infinities”….simple put : there is an infinite number of integers, half of those are multiples of two, but there is an infinite number of multiples of two, like wise multiples of any
    integer including the integer at infinity. From this can we say that there is an infinite number of infinities? Bright kids as young as ten will play with that idea and have fun. BTW I don’t know the answer.

    The best definition of time that i ever heard was from a ten year old: “It’s what separates two events that do not happen simultaneously.”

    Our plumber is a great bloke…so laid back that he is nearly horizontal. But believe me my mother wasn’t referring to me being relaxed…oh no!

    Talking of cow droppings….when dry they make wonderful skimmers!

  12. Ursula Says:

    Magpie, I have never been good at skimming but I do know that a DRY cowpat can be stood upon without consequences.

    Reading that you “love playing with concepts” in your quest to keep the young interested a book title comes to mind “Where were you, Robert?” by Hans Magnus Enzensberger.

    When first introduced to the concept of infinity I was nearly driven to the brink of my sanity. There I’d be, a young girl, lying in my bed, and instead of counting sheep I was contemplating infinity till I was frightened out of my wits. No wonder sleep eludes me to this day.

    U

  13. Judy Harper Says:

    I’m trying to get to know my fellow LBC people. I enjoyed this post. Funny AND interesting. Looking forward to Friday.

  14. magpie11 Says:

    Welcome… I think I know what Conrad’s Collection consists of….

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