If tomorrow everything was doubled in size...

....would we know it?

My father in law proposed this question to me last night. It's from his
college physics class. If everything were doubled in size, would we know it?
My pond-soggied brain was enjoying the cabernet and wasn't sure of the
answer. He says because of the inverse square law, we would know it.

Help a non-physicist out.


--
BV
Webporgmaster of iheartmypond.com
Check out the IHMP forums, ihmp.net/phpbb
I'll be leaning on the bus stop post.

"Benign Vanilla" wrote in message
...
...would we know it?

My father in law proposed this question to me last night. It's from his
college physics class. If everything were doubled in size, would we know it?
My pond-soggied brain was enjoying the cabernet and wasn't sure of the
answer. He says because of the inverse square law, we would know it.

Help a non-physicist out.

The volume (and hence the mass) of a three dimensional body
goes as the cube of the size (radius). So doubling all your
dimensions would leave you eight times more massive and
hence eight times heavier.

This is why an elephant is not just a big mouse -- the cross
sectional thickness of its bones must be much more than a
simple proportionate scaling would indicate.

If your size were to double overnight, your first hint might
be when you break a leg trying to get out of bed in the morning.

You know, I thought of this a while ago.....what if the universe expanding
was making everything expand in size at the same time - would we notice?

I'm not a great physicist myself so I can't really explain why we would or
wouldn't notice but it's my gut feeling that there would have to be
something noticeable as a result of a situation where we double in size.....

- Jeff
"Benign Vanilla" wrote in message
...
...would we know it?

My father in law proposed this question to me last night. It's from his
college physics class. If everything were doubled in size, would we know
it?
My pond-soggied brain was enjoying the cabernet and wasn't sure of the
answer. He says because of the inverse square law, we would know it.

Help a non-physicist out.


--
BV
Webporgmaster of iheartmypond.com
Check out the IHMP forums, ihmp.net/phpbb
I'll be leaning on the bus stop post.

Benign Vanilla wrote:
...would we know it?


Gas prices would double.

From BV

It's from his college physics class. If
everything were doubled in size, would
we know it?

When my first old lady doubled in size, i certainly knew it. It was a
case study in research of massive bodies.

Old labrat
oc

"Greg Neill" wrote in message
.. .
"Benign Vanilla" wrote in message
...
...would we know it?

My father in law proposed this question to me last night. It's from his
college physics class. If everything were doubled in size, would we know it?
My pond-soggied brain was enjoying the cabernet and wasn't sure of the
answer. He says because of the inverse square law, we would know it.

Help a non-physicist out.

The volume (and hence the mass) of a three dimensional body
goes as the cube of the size (radius). So doubling all your
dimensions would leave you eight times more massive and
hence eight times heavier.

You will be much more heavier on earth, as the mass of earth also increased 8 fold!


--
md
10" LX200GPS-SMT
ETX105
www.xs4all.nl/~martlian

"md" not given to avoid spam wrote in message ...

"Greg Neill" wrote in message
.. .
"Benign Vanilla" wrote in message
...
...would we know it?

My father in law proposed this question to me last night. It's from his
college physics class. If everything were doubled in size, would we know it?
My pond-soggied brain was enjoying the cabernet and wasn't sure of the
answer. He says because of the inverse square law, we would know it.

Help a non-physicist out.

The volume (and hence the mass) of a three dimensional body
goes as the cube of the size (radius). So doubling all your
dimensions would leave you eight times more massive and
hence eight times heavier.

You will be much more heavier on earth, as the mass of earth also increased 8 fold!

Ah! Well done.

The Earth will be eight times more massive, but you'll be
twice as far from its center. Gravity is an inverse square
relationship, so the net result will be to double the
gravitational constant -- r^3 for the mass and r^-2 for the
radial change for a net of r^1. Since r doubles, you'll feel
twice as heavy as otherwise, or 16 times as heavy (8 x 2)
overall.

"Greg Neill" wrote in message
.. .
"md" not given to avoid spam wrote in message
...

"Greg Neill" wrote in message
.. .
"Benign Vanilla" wrote in message
...
...would we know it?

My father in law proposed this question to me last night. It's from his
college physics class. If everything were doubled in size, would we know it?
My pond-soggied brain was enjoying the cabernet and wasn't sure of the
answer. He says because of the inverse square law, we would know it.

Help a non-physicist out.

The volume (and hence the mass) of a three dimensional body
goes as the cube of the size (radius). So doubling all your
dimensions would leave you eight times more massive and
hence eight times heavier.

You will be much more heavier on earth, as the mass of earth also increased 8 fold!

Ah! Well done.

The Earth will be eight times more massive, but you'll be
twice as far from its center. Gravity is an inverse square
relationship, so the net result will be to double the
gravitational constant -- r^3 for the mass and r^-2 for the
radial change for a net of r^1. Since r doubles, you'll feel
twice as heavy as otherwise, or 16 times as heavy (8 x 2)
overall.


exactly :-)

but then, now I reread the question, it just says that size doubles. What if masses remain the
same (density decreases). Would we notice?
--
md
10" LX200GPS-SMT
ETX105
www.xs4all.nl/~martlian

"md" not given to avoid spam wrote in message ...


but then, now I reread the question, it just says that size doubles. What if masses remain the
same (density decreases). Would we notice?

Sure, your weight would be 1/4 what it was before since you'd be twice
as far from the center of the planet.

Do you fly?
Asked the snail of the grissaile.

"On occasion, the occasion, rare.
And you?"
~ Grissaile

"Who, me? O, not. But do
Ask Ms.
Sea Gull. She does."
~ Moi

“You must always demand such allowances,
A mysterious
Vault
Of unscripted scenes, undiscovered passages.�
~ Ms. Sea Gull

She further explained to me,
She’d made plain to herself this thing, where the question
Stood ready to engage,
All blushing and radiant, eager to ask,
“How?�

~ Waves
Overlapping ~

An old device for measuring time,
Consisting of two globular vessels,

A narrow neck connecting,
Through which a quantity of sand, mercury, or water

Runs from the upper vessel to the lower
During a stated interval of time, usually

An hour…

~ Waves
Lapping ~
Our vessel ~

An old time-measuring device,
Consorting two globular vessels, a basin

Floating a narrow neck connecting
A quantity of sand, mercury, or water

Delivering a faster vessel toward the slower
During a mean Greenwich interval of time, usually

A second-handed account, recounting
Our hours together, yesteryear, measured, crafted

Here, bottled in a message, cast adrift across
Time's waterways, in hope of washing ashore,

A tried, true tide, you, me, as once we, together
Knew, our hours ours, counted as

Castaways, our island. A lighthouse
Beacon beckons. Only seconds, my astrolabe

Measures, away today...

*
_______
Blog, or dog? Who knows. But if you see my lost pup, please ping me!
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