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Weight, How is That Possible?
Science
Science brain teasers require understanding of the physical or biological world and the laws that govern it.Science
We all know that if you weigh yourself on the moon, it is less than your weight on the Earth. Can you tell me something that actually weighs more on the moon than on Earth?
Answer
A helium filled balloon; or a balloon filled with any gas lighter than air.Earth's atmosphere causes a helium balloon to float, thus making it impossible to weigh. On the moon, the lack of atmosphere causes the balloon to sink, allowing it to be weighed. It will only weigh a little bit, but will still be heavier than on earth.
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Yay 1st 1!
good teaser
good teaser
Wow, that's interesting. Good teaser!
Except that the helium balloon would burst dut to the pressure difference.
I'm not sure this one's quite right. I hope I don't start anything here but...
The reason the balloon floats on Earth is because, while it does have weight (and can, in fact, be weighed, e.g. in a vacuum) that weight is less than that of the air around it (hence "lighter than air")
If it does in fact "fall" on the moon, that is because there is no atmosphere. (I think it would have to be quite close to the moon's surface for this to happen, because of the moon's weak gravitational field)
Weight is a product of mass and gravity. The mass of the balloon is constant (it is always made up of the same molecules). Gravity is lower on the moon than the Earth.
Therefore, the weight of the helium balloon is less on the moon than it is on the Earth!
(I also agree with Numpty, although I was assuming it was a "special" balloon made of some NASA style rubber that can withstand such pressure differences )
The reason the balloon floats on Earth is because, while it does have weight (and can, in fact, be weighed, e.g. in a vacuum) that weight is less than that of the air around it (hence "lighter than air")
If it does in fact "fall" on the moon, that is because there is no atmosphere. (I think it would have to be quite close to the moon's surface for this to happen, because of the moon's weak gravitational field)
Weight is a product of mass and gravity. The mass of the balloon is constant (it is always made up of the same molecules). Gravity is lower on the moon than the Earth.
Therefore, the weight of the helium balloon is less on the moon than it is on the Earth!
(I also agree with Numpty, although I was assuming it was a "special" balloon made of some NASA style rubber that can withstand such pressure differences )
leftclick is correct. The Helium does in fact weigh less on the moon as well. It is just that on the moon there is no heavy atmosphere for it to float upon.
And, While we're being picky and scientific, it is not true that thebaloon cannot be weighed on earth. If you attach it to a spring balance, you will find out that it has negative weight, or - as the fly boys call it - "lift."
Our science museum weighs gases [in sealed jars] in a vacuum. Lower gravity would keep to proportions. In a dome pressurized to one atmosphere, a balloon would have its same lifting capacity, but its ascent would be slower because whole air accelerates into volume of space beneath the rising balloon under weaker gravity.
I voted easy and boring because it is.
swaff thinks hes cool.....that is all i will say you guys try to determine what I mean by thinks
Well I kinda liked it until I read the comments. I tend to agree that the answer is wrong and it should have been a science teaser anyway. I should have thought a bit further and realised that with a bit of physics, the mass of the molecules can be calculated and muliplied by the gravitational constant. You don't need to weigh it to determine its weight! Go Mathematics!!!
Not really situation more of a science one but still it was ok 7/10
Very clever, Keep up the good work!
Yup, above comments are right. At least get a teaser's answer right before you submit it.
I need some of that NASA rubber for, well, you get the idea....
I need some of that NASA rubber for, well, you get the idea....
yes and no.
clever for evryday talk but not very good for a scientist.
clever for evryday talk but not very good for a scientist.
I agree that its not technically "right" but I think he means accouting for atmospheric differences between the Earth and Moon too, not just gravity. More of a trick for me but still works.
I believe this version is fine, and it DEFINITELY belongs in this category. Now somebody should make a version refuting this and put THAT in the science category.
All I can say is "Ho Hum!" (
I'll check it out on my next trip to the moon. And to GW
Didn't get it, but I'm not a science kinda gal. Lots of information in the comments that I didn't know.
If, as unclemyke says, the balloon has a negative weight on Earth, but a positive weight on the Moon due to the lack of atmosphere, then surely it does, in fact, weigh more on the Moon than on Earth?
@spikethru4 - The balloon on earth doesn't really have negative weight. It's just that the buoyancy of the balloon gives it the appearance of negative weight. You still weigh the same either on land or in the water, but your buoyancy in water gives the impression that you weigh less. If you measure the weight of a balloon in a vacuum chamber (this removes any buoyancy effect and the balloon will not float) both on earth and on the moon, the weight will be significantly less on the moon.
Thanks, @elentir, that's a good explanation. I wasn't altogether comfortable with the concept of 'negative weight', since the mass must be positive and the gravitational force is positive, therefore weight must also be always positive. It's clear now that the air resistance is a separate force that counteracts the weight, giving a resultant force in the opposite direction (i.e. upwards).
So according to that reasoning, a ping pong ball floating on water has no weight either, until you take it out of the water? Being buoyed within/on top of a mass of a substance less dense than itself does not negate the fact that an object has weight.
Not at all. The ping pong ball's weight is only one force acting on it. The buoyancy of the water is another force. If the ball is resting on top of the water, then the two forces are equal and opposite.
OK teaser. I did not get it and no idea what the answer was. Science is one of my worst subjects.
Nice teaser, my first thought was a light gas, but couldn't work out how to weigh it without actually compromising the experiment. A helium balloon would be ideal!
With the reasoning stated, many things have more "weight" on the moon than on Earth. Put a scale on the bottom of the Dead Sea, and I would not be able to touch it, therefore I would have "negative weight".
The atmosphere is like any other medium, including water. Normally we ignore it's effects, because they are negligible, but in this case, you can't say the gas has less weight just because of them.
I see where the teaser is going, and I hate that we're all nitpicking so much, but in this case, I think it's too much of a non-science stretch to ignore in the Science category.
The atmosphere is like any other medium, including water. Normally we ignore it's effects, because they are negligible, but in this case, you can't say the gas has less weight just because of them.
I see where the teaser is going, and I hate that we're all nitpicking so much, but in this case, I think it's too much of a non-science stretch to ignore in the Science category.
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