Does Your Weight Change Between Noon and Night Due to the Sun's Position?

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In summary: What is relevant is the relationship between the mass of the Earth, the mass of the sun, and the distance between them. This relationship is what dictates the strength of the gravitational force between the two bodies. The mass of the Earth and the sun are constants, while the distance between them is constantly changing due to the Earth's orbit. When the Earth is closer to the sun, the force of gravity is stronger, and when it is farther away, the force of gravity is weaker. This change in distance is what causes the change in weight, albeit a tiny change. In summary, the change in weight at night compared to during the day is due to the change in the distance between the Earth and
  • #1
ayan_dg
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At noon when Sun is directly over my head, the gravitational pull of Earth & Sun on me are in opposite direction but during night as the Earth is between me & Sun , the attraction of Earth & Sun are in the same direction. So at night my weight should be more than in noon. But it does not happen actually. Please explain why ?
 
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  • #2
The difference in weight is most likely negligible but you would expect it to be there. I hear you gain 2cm of height in the daytime until you sleep again.
 
  • #3
As stated above, gravitational changes are neglible (relative change is 6x10^-4).
Far more significant is the change in mass due to flow of food and especially water.
 
  • #4
First off, your premise is flawed. You would not expect to weigh more at night. Any effect the Sun has on your weight would be due to tidal forces, and for the same reason we have two tidal bulges, the tendency would be to weigh less at noon and midnight, and more at sunrise and sunset.

Secondly, as already mentioned, the Sun's effect on your weight is tiny.
 
  • #5
Janus said:
First off, your premise is flawed. You would not expect to weigh more at night. Any effect the Sun has on your weight would be due to tidal forces, and for the same reason we have two tidal bulges, the tendency would be to weigh less at noon and midnight, and more at sunrise and sunset.

Secondly, as already mentioned, the Sun's effect on your weight is tiny.

Although tiny, in astrology, when a man was born, day or night may have some effect, I ve heard.
 
  • #6
pixel01 said:
Although tiny, in astrology, when a man was born, day or night may have some effect, I ve heard.

Is astrology based on science?
 
  • #7
jobyts said:
Is astrology based on science?

Some astrologists claim so. I am not sure. Can you prove that astrology is not based on science?
 
  • #8
pixel01 said:
Some astrologists claim so. I am not sure. Can you prove that astrology is not based on science?

The methodology:

Science - Observation => Hypothesis => Controlled Observation => Conclusion
Astrology - Conclusion = Hypothesis =/= Observation
 
  • #9
pixel01 said:
Some astrologists claim so. I am not sure. Can you prove that astrology is not based on science?

If astrology was based off of science, we would expect the predictions of astrology to be correct most of the time, since for them to be scientific, they would have to be based off of evidence.

So, astrology is not scientific since the conclusions are made without any evidence, (There is no hard evidence that the stars affect our lives.) and the conclusions do not correspond with observation. (The predictions are not always correct. If they are correct, it is not with enough regularity to assume anything other than luck as the cause.)
 
  • #10
First off, your weight does in fact change, you are not imaging it.

Second: The difference is tiny. Easy to calculate, but tiny. Remember, the Moon moves the tides, not the Sun. Not because the Sun does not create an effect, but because it is swamped by the larger gravitational effects of the Moon.

Remember, the gravity effects of one body on another are proportional to the distances. So while the Sun is Really, REALLY big, it is so far away that unless you have a planetary mass, the effect on you is almost non-existant compared to say the mass of the moon which is trivial by comparison but because it is so much closer the effect is vastly (if still tiny) larger.

When in doubt, check your local tide charts. At Neap tide you weigh a tiny amount less, and at Ebb tide you weigh a tiny amount more.
 
  • #11
Answer

Heres Why: I believe this is correct, not fully sure though.

Contrary to what someone here said about your weight, weight is not determined by the force YOU push down on the scale. Rather, it is the force the SCALE pushes up on you. That said, think of the problem. You have earth. You have the sun at the center. The sun pulls you toward itself. simple right? so now u have a force going up (assuming you picture this as the sun above the earth). When you weigh yourself during the day, the scale pushes up as well. So you can mathematically add the forces together to get one value. Now think at night. Instead, you have the force of the sun pulling up, but the force the scale does on you goes DOWN. Thus you weigh less during the night than at day. It would help to have an actual physics instructor here to check our work.
 
  • #12
False

mda said:
As stated above, gravitational changes are neglible (relative change is 6x10^-4).
Far more significant is the change in mass due to flow of food and especially water.

FALSE, remember the CONSERVATION OF MASS = the mass of a closed system remains CONSTANT no matter what processes are occurring inside that system.
 
  • #13
wysard said:
First off, your weight does in fact change, you are not imaging it.

Second: The difference is tiny. Easy to calculate, but tiny. Remember, the Moon moves the tides, not the Sun. Not because the Sun does not create an effect, but because it is swamped by the larger gravitational effects of the Moon.

Remember, the gravity effects of one body on another are proportional to the distances. So while the Sun is Really, REALLY big, it is so far away that unless you have a planetary mass, the effect on you is almost non-existant compared to say the mass of the moon which is trivial by comparison but because it is so much closer the effect is vastly (if still tiny) larger.

When in doubt, check your local tide charts. At Neap tide you weigh a tiny amount less, and at Ebb tide you weigh a tiny amount more.


What this person is trying to use is the relationship between Force of gravity between two bodies. This is known as F = G (constant) m(body 1) x m(body2) / (distance between the two centers of mass ) Squared. simply seen as F = Gm1m2/ r^2. If you look at it this way, you would think that the farther a body is away, the less force gravity has on it. Logical right? but, in this situation, we need to realize that your weight is not how much u push on that darn scale. it's how much it pushes up on you. so you look for the situation that maximizes the force in the same direction.
 
  • #14
puopg said:
FALSE, remember the CONSERVATION OF MASS = the mass of a closed system remains CONSTANT no matter what processes are occurring inside that system.

The human body is not a closed system... think about it.
 
  • #15
If you think the sun is big, take a look at these other stars:



wysard said:
So while the Sun is Really, REALLY big, it is so far away that unless you have a planetary mass, the effect on you is almost non-existant compared to say the mass of the moon which is trivial by comparison but because it is so much closer the effect is vastly (if still tiny) larger.
 
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1. What causes weight fluctuations between noon and night?

Weight fluctuations between noon and night can be caused by a variety of factors, such as food and fluid intake, digestion, and physical activity. Additionally, hormones and circadian rhythms can also play a role in weight changes throughout the day.

2. Is it normal for weight to be higher at night?

Yes, it is normal for weight to be slightly higher at night compared to the morning. This is due to the accumulation of food and fluids throughout the day, as well as the effects of gravity on the body.

3. How much weight difference is considered normal between noon and night?

The normal weight difference between noon and night can vary depending on individual factors, but a fluctuation of 1-2 pounds is generally considered normal. However, if there is a sudden and significant increase in weight, it may be a sign of a larger issue and should be discussed with a healthcare professional.

4. Does sleeping affect weight at night?

Sleeping can affect weight at night in a few ways. First, during sleep, the body burns fewer calories compared to being awake and active. Additionally, sleep deprivation can disrupt hormones related to appetite and metabolism, potentially leading to weight gain. However, adequate and quality sleep is important for overall health and can also aid in weight management.

5. Can stress impact weight at noon and night?

Yes, stress can impact weight at noon and night. Chronic stress can lead to increased levels of the hormone cortisol, which can contribute to weight gain. Stress can also affect eating habits, leading to overeating or choosing unhealthy foods, both of which can impact weight. Finding healthy ways to manage stress, such as exercise or relaxation techniques, can help mitigate its effects on weight.

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