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Because everything else is also moving.
even if you close your eyes the effect is the same
Why would that make a difference?
thecurious one, I have a question. HOw many chromosomes are there after telphase? 46 or 92?
Do you feel like you’re traveling 250 km/h on an airplane? Unless you’re accelerating significabtly, you can’t really feel it unless you can clearly see that you’re moving at a different speed than your surroundings. (Look up inertial reference frames.)
no. no and no
it has nothing to do with the frame of reference, it has nothing to do with seeing things around you. forget “dizziness, that was a bad way of putting the question, think in terms of “feeling” the turning.
the situation will be the same if the merry-go-round is located alone in outer space, just as the earth is
here is an easier way to look at the problem, instead of talking about human perception:
say you have a measurement device with you that measures centrifugal “force”.
although the merry-go-round (now relocated in outer space, off the earth)is rotating at a speed of say 5 miles per hour, and the earth is rotating at 1,000 miles per hour, the centrifugometer will measure over 10,000 (something like that, i didnt actually calculate it) times the amount of centrifugal force on the m-g-r than it does on earth. why is that?
if the m-g-r would move at 1,000 miles per hour (as does the earth) you would be instantly and violently thrown off, even if the m-g-r had the same gravity as the earth does. why arent we thrown off the earth?
the answer is a matter of very elementary (1st year high school or even less) beginning physics.
you need to know the basic definition of “accceleration”, and the difference between “velocity” and “speed”
Centrifugal force is fictitious. What you are talking about is centripetal force. And by the nature of circular motion, you’re ALWAYS accelerating.
yes pegger, notice my use of the quotation marks: centrifugal “force”.
nevertheless, because i am not speaking to a group of physicists it is perfectly acceptable to use the common term: centrifugal force, as it IS an “apparent’ or “virtual” force though not a force in the strict sense.
and yes you are always accelerating when moving in a circle. do you have an answer to the question: why is the centrifugal (if you prefer: centripital) force greater on the slowly moving mgr than on the rapidly moving earth?
i am not speaking to a group of physicists
With Pegger here, I’m not so sure…:)
Centripetal force doesn’t have much to do with the dizziness. While it’s true that the earth is moving more rapidly than the merry-go-round, in fact, one’s ANGULAR velocity is much, much less than on a merry-go-round. This is why you wouldn’t get dizzy.
right
the angular velocity is the only parameter that involves acceleration, and therefore the perception of movement.
the mgr goes through a full circle in about 1/2 a minute while the earth rotates through a full circle in 24 hours.
so in terms of RPM (revolutions per minute) them mgr is actually moving about 2,500 times faster than the earth.
thecurioseone
no
the centripital force is unnafected by gravity
it is true that the net force on an object situated on a rotating body (the net force acting to keep the object on the body or away from the body, (ie the weight, in simple terms) is influenced both by the force of gravity vs the rotational (angular) acceleration, but those two parameters have zero influence on each other.
in other words, a device which measures centripital force would give a reading thousands of times greater on the mgr than on the earth even if the mgr would somehow have a pull towards the center equivalent to earths gravity. that was the essence of the question as i restated it. the original question was not clear as i should have not used “dizziness” as the main differential factor between the two cases. i tried a couple of times to fix that.
Beta oxidation is when saturated fatty acids are broken down and two carbon units are removed with each turn of the cycle. The oxidation of fats results in a large quantity of water so camels who don’t have adequate access to drinkable water obtain their water requirements from the complete oxidation of fats.
curiousone;
to put it another way, even if the earths gravity were to suddenly completely cease, we would not go flying off the earth. in fact the centrifugal force would be so negligible as to be “practically” non-existent. picture an ant sitting on the end of the HOUR hand of a smoothly moving analog clock (not one that “ticks”). how much centrifugal force is that ant experiencing from the movement of the hand. that hand is moving at the same angular acceleration as the earth.
[of course you would have to make SOME kind of effort to stay put such as touching any object attached to the earth, say a tree. the friction of the slightest touch would keep you from slowly eventually floating away, as long as you didnt make any kind of motion against the earth, such as walking.]
What is beta oxidation, and why does it help camels?
see here:
http://www.theyeshivaworld.com/coffeeroom/topic/the-camel-and-the-desert
Beta oxidation is when saturated fatty acids are broken down and two carbon units are removed with each turn of the cycle. The oxidation of fats results in a large quantity of water so camels who don’t have adequate access to drinkable water, obtain their water requirements from the complete oxidation of fats.
Centripetal force is not a force that exists in its own right. In order for an object to remain in circular motion, there needs to be a force ALREADY pulling the object towards the centre of the circle to PROVIDE centripetal force.
For example, in swinging a yoyo in a circle, the force of tension provides centripetal force. When a car drives around a sharp curve, the force of friction provides centripetal force. And when a person stands on the Earth, the force of gravity provides centripetal force.
Therefore, if Earth’s gravity turned off, a person would simply continue to follow his tangential velocity and fly off into space. (Of course, the whole planet would have disintegrated as well, so you might not notice.)
(Of course, the whole planet would have disintegrated as well, so you might not notice.)
“…it would probably have been a great satisfaction to her to know that in a minute and a half or so he would suddenly evaporate into a whiff of hydrogen, ozone and carbon monoxide. However, when the moment came she would be too busy evaporating herself to notice it.”
tee hee
You would not fly off into space
You would slowly rise based on the angular velocity
The centripital force is supplied by the friction as i described
And curiousone you are way off. the second equation is only a particular application of the general
Equation
Gravity is in no way reqired for friction
Friction can in fact act in opposition to gravity
This is basic
feivel – a person would move according to his tangential velocity, not his angular velocity. Angular velocity is only pertinent to circular motion, and he would no longer be spinning – that’s the point. A person’s tangential velocity at the surface of the earth is almost 30 km/sec! I’d call that flying, not “slowly rising”…
But you’re right that gravity isn’t required for friction. Normal force is required for friction. While it’s true that normal force often comes from gravity, it doesn’t have to! It’s another one of these forces that doesn’t really exist in it’s own right…
when writting the fourth quantum number Ms ther’s is a value of 1/2 or -1/2 does it makes a difference which electron gets which value?
pegger
let me give it one more try
if you dont agree with the analysis we can leave it as a disagreement
indeed you stop spinning.
which has no effect on your tangential movement which is directly perpendicular to the direction of the force of gravity
you will continue to move in a linear 30k/s exactly as you did before due to there being no force to act to change your momentum. as you continue to move in a straight line tangential to the earth at 30k/s, the earth continues to move below you at a speed of 30k/s as before thus there being no change in your situation relative to tangential movement in relationship to the earth.
what does change is that as you say you are no longer spinning. what does that mean? it means that your ANGULAR VELOCITY is now null, you areno loner changing direction in concert with the earths angular velocity. your angular velocity has now become zero since the source of the centripital force has been removed.
but now the difference between your angular velocity (zero) and the earths angular velocity (a very small 1 revolution per 24 hours) and you will gradually rise away from the spot of earth below you as it continues to change direction, and you do not.
but as far as your tangential movement relative to the surface of the earth nothing has changed by the cessation of gravity. you are moving at 30k/s (as a result of your momentum which no force has altered, and the earth is moving under you at that same 30k/s just as before, as similarly no force has acted to change this.
you will slowly rise as the the earth spins and you are no longer spinning with it.
if you dont get it, try this thought experiment:
you lift yourself with a crane to 500 feet above the earth (the 500 feet-crane part of this isnt necessary but it might help to prevent certain misunderstandins) you are equipped with downward pointing thrusters exactly equal to the effect of gravity on you.
as the crane releases you, you turn on the thrusters. you have now eliminated all centripital force and are no longer “spinning with the earth” are you going to suddenly fly away at 1,000 miles per hour? of course not, but you will very slowly become more distant from the earth as the earth contues to turn.
feel free to submit your rebuttal but i quit, thanks for the interesting discussion
Reasons people dont go on a second date?
from the cornell dept of astronomy:
link to the “article”:
http://curious.astro.cornell.edu/question.php?number=284
What would happen if the gravity on Earth was suddenly turned off?
….In buildings, people would start floating gently upwards until they bumped into the ceiling. Outdoors, however (or in buildings with GIANT ceilings), things would start floating away from the Earth gently but eventually go much faster, as their straight lines took them farther and farther away from the circular path that the spinning Earth takes.
…In fact, the force you would need to hold on and keep yourself from flying away from the Earth is very weak, only about 0.3% as strong as the force of gravity (and even weaker away from the equator).
emphasis is mine
What would happen if the gravity on Earth was suddenly turned off?
….In buildings, people would start floating gently upwards until they bumped into the ceiling. Outdoors, however (or in buildings with GIANT ceilings), things would start floating away from the Earth gently but eventually go much faster, as their straight lines took them farther and farther away from the circular path that the spinning Earth takes.
…In fact, the force you would need to hold on and keep yourself from flying away from the Earth is very weak, only about 0.3% as strong as the force of gravity (and even weaker away from the equator).
I think you forgot some emphasis.
feivel – My rebuttal shall be limited to the sentence you replaced with a “…” from that article:
“Things not attached to the Earth in any other way would fly off into space in a straight line that would take them away from the surface of the Earth.”
Thanks for the discussion.
Eventually they would go much faster
Has nothing to do with this discussion
that is referring to the eventual perceptual conversion
of the perceived movement of the object in question from that
Relative to the surface of the earth
to that relative to the earth as a whole body
which would be on the order of weeks to become significant.
As to your rebuttal pegger i am disapointed
I thought you would exhibit some honesty
We all can be wrong sometimes
the article was quite clear as to the nature of what was meant by
flying.
His description was not at all compatible with
a veocity of 30k per second.
I of course wholey agree with your rebuttal pegger
I always said one would go flying off the earth
I only said it would be slowly not at 30 kilometers per second
Which is not compatible with the description from cornell
I truly am sorry you chose to end the discussion like this
Pegger-
feivel-
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As the atmospheric pressure decreased, all water would begin to boil (the precise temperature at which each ocean, river and lake boiled would depend on temperature, salinity, latitude and elevation) until there was no water left on Earth.
Aha, I think I see where we differ in this ridiculous hypothetical discussion. You see, I was assuming that if gravity was turned off, the planet disintegrated. It’s pretty much impossible to predict how the laws of physics will behave if you’re starting from the premise that certain important laws will be ignored.
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