[Richard_pics]

Basically im at work, but bored and in a thoughtful mood, so i thought i pose the question below, as i cant seem to find anything clear on google.

Drinking When Riding. The Bike Gets Lighter, But Does The Overall Mass Go Up, Or Stay The Same?….

When you drink, your bottle and bike get lighter. But as you take the water on board, does the mass overall stay the same, or does it get lighter?!

Answers below!….

Topic

[hawkinspeter]

Canyon48 wrote:

John Smith wrote:

True. Your weight could go up or down depending on a number of things, for a start the gravitational changes as you move and as time passes 

https://www.technologyreview.com/s/614741/can-earths-gravity-really-be-affected-by-changes-in-the-seasons/

And (according to Einstein) how fast you’re going…!

If you’re going to get all relativistic, then you’d have more mass at the top of a hill (due to potential energy) than the bottom. However, you may have less weight as the hill-top will probably have slightly lower gravity.

[Canyon48]

John Smith wrote:

True. Your weight could go up or down depending on a number of things, for a start the gravitational changes as you move and as time passes 

https://www.technologyreview.com/s/614741/can-earths-gravity-really-be-affected-by-changes-in-the-seasons/

And (according to Einstein) how fast you’re going…!

[John Smith]

True. Your weight could go up

True. Your weight could go up or down depending on a number of things, for a start the gravitational changes as you move and as time passes 

https://www.technologyreview.com/s/614741/can-earths-gravity-really-be-affected-by-changes-in-the-seasons/

[mdavidford]

The mass obviously increases.

The mass obviously increases. Because cake stops.

[Though not in the current circumstances.]

[Secret_squirrel]

DoctorFish wrote:

The whole system (you, bike, water) gets lighter throughout the ride as you sweat, pee, breath out moisture.

By drinking you are just moving weight mass from your water bottle in to you.

FTFY – otherwise 100% correct and model answer.

[Welsh boy]

Of course, you could always

Of course, you could always weigh yourself and your bike just before you set off and then again as soon as you finish your ride to find out.  On a warm day and a ride of a couple of hours, assuming you are wearing decent cycling kit which doesnt hold too much sweat,  I guess you would probably lose about 1kg.

[Sriracha]

To answer the actual question
To answer the actual question posed, the mass is unchanged.

[DoctorFish]

The whole system (you, bike,

The whole system (you, bike, water) gets lighter throughout the ride as you sweat, pee, breath out moisture.

By drinking you are just moving weight from your water bottle in to you.

 

[Dangerous Dan]

That all depends on how much

That all depends on how much you perspire.  The total mass will decrease, but as others have pointed out, not by very much.

[Welsh boy]

By drinking, all you are

By drinking, all you are doing is redistributing the mass (ie from the bottle into you) so any water leaving your body (sweat, snot, spit, respiration) is going to lower the overall mass.

[Richard_pics]

But are you loosing more mass

But are you loosing more mass in sweat than you are taking on board? or less?

 

[Dangerous Dan]

Try a search for “respiration

Try a search for “respiration”.

If you are breathing in oxygen (O2) and breathing out carbon dioxide (CO2) you are losing mass.  You are probably also losing water through sweating and the moisture in your breath.

[Author]

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