Does a sealed lorry containing budgies weigh less if they are flying than when sitting on perches?
Its an old conundrum, and one that I feel has never been answered properly.
Answers:
the only way a bird can fly in the first place is because their wings are pushing down on the air.
the force of the air pressure downward equals their weight.
the total weight will be the same!
it's called basis conservation of energy in a closed system
Yes it does. When they are perched they weigh a little, but when flying they weigh less than the air.
Oh god, I hate these questions, its like that old myth that if you are in a falling lift, you should jump just before you hit the bottom, then you won't be injured.
I would say, if you are talking about physically raising the lorry and placing it stationary on a big set of scales, it would weight exactly the same as if the budgies were sitting down.
But I would have thought, in terms of pressure applyed on the road, that it would be less if the budgies were flying.
Argh, I don't know!!!
the lorry weighs exactly the same, and so will the contents, but what it'll show on a scale depends on how many budgies will be sitting down - a scale won't be able to weigh the flying ones. ;)
Yes.
if you drive down the motorway you will see lorries stoped at the side of the road and the driver knocking the sides with a stick
and if you look carefully you will see a sign saying birds in transit
i honestly dont know. if you put a bird inside a balloon, and wigh it while it flies, maybe the downward thrust of the air will push the balloon down and cancel the lift? dunno.
thanks dnnyo. should i be convinced though?
it weighs the same, when the budgies are flying they push the air creating a downforce equal to their weight on the floor of the lorry.
I agree with the line that they all weigh the same, but if the whole lorry was placed stationary on a big scale, it would show heavier when the birds were sitting. When they are flying they do use their wings to push down air with the same force required to keep them up, but due to friction in the air, not all that downward force is transfered perfectly onto the lorry platform. Therefore, the flying ones apply less downforce to the lorry, despite the the law of conservation of energy, because some of the energy is turned into heat and sound by friction in the air.
Surely not!
you are talking about two different masses, mass of the lorry and mass of its contents.
Since P=mg, P being the weight force, m - mass, and g - gravitational acceleration, weight will be proportional of the mass.
the mass of lorry in either case remains the same
but in case when birdies are sitting on perches, they will apply pressure to the lorry, thus their mass will add to the lorry's mass. You'll just be counting their weight combined, P = ( m1 + m2 )g
however, if you manage to launch this lorry into open space, that is, place it in vacuum, their mass will equal to m1+m2, but they will effectively weigh nothing, since g will be zero and P will be zero. I think--------
actually physics is the only school subject i've never been good at
The weight is the same if they are holding constant altitude in the lorry. For every action, etc. etc.
If they are climbing, the lorry will be heavier, since they are applying extra lift to their wings beyond their weight. If descending, the lorry is lighter.
LOL
Yes, I would say it definitely weighs less albeit a very small amount!
I suppose it would weigh the same otherwise you could put a helicopter in an enclosed container bolt it down to the bottom and it would fly with no visible mean of support.
Yes.
No.
Get a set of scales, and place a cup of water on them, when everything has settled down, put your finger in the water and see what happens.
Sea serpents remain alive in the arctic island ?
Moon Sighting in UK?
Stuck for an idea.?
how many solar eclipses in 2005?
Why do people get double chins?
What are the chances of Jonathon woss becoming extinct.?
Scientific question..Is there such thing as naturally black hair? Is it just intense dark brown ?
How many sides, corners, edges are there in cube, cuboid?
Answers:
the only way a bird can fly in the first place is because their wings are pushing down on the air.
the force of the air pressure downward equals their weight.
the total weight will be the same!
it's called basis conservation of energy in a closed system
Yes it does. When they are perched they weigh a little, but when flying they weigh less than the air.
Oh god, I hate these questions, its like that old myth that if you are in a falling lift, you should jump just before you hit the bottom, then you won't be injured.
I would say, if you are talking about physically raising the lorry and placing it stationary on a big set of scales, it would weight exactly the same as if the budgies were sitting down.
But I would have thought, in terms of pressure applyed on the road, that it would be less if the budgies were flying.
Argh, I don't know!!!
the lorry weighs exactly the same, and so will the contents, but what it'll show on a scale depends on how many budgies will be sitting down - a scale won't be able to weigh the flying ones. ;)
Yes.
if you drive down the motorway you will see lorries stoped at the side of the road and the driver knocking the sides with a stick
and if you look carefully you will see a sign saying birds in transit
i honestly dont know. if you put a bird inside a balloon, and wigh it while it flies, maybe the downward thrust of the air will push the balloon down and cancel the lift? dunno.
thanks dnnyo. should i be convinced though?
it weighs the same, when the budgies are flying they push the air creating a downforce equal to their weight on the floor of the lorry.
I agree with the line that they all weigh the same, but if the whole lorry was placed stationary on a big scale, it would show heavier when the birds were sitting. When they are flying they do use their wings to push down air with the same force required to keep them up, but due to friction in the air, not all that downward force is transfered perfectly onto the lorry platform. Therefore, the flying ones apply less downforce to the lorry, despite the the law of conservation of energy, because some of the energy is turned into heat and sound by friction in the air.
Surely not!
you are talking about two different masses, mass of the lorry and mass of its contents.
Since P=mg, P being the weight force, m - mass, and g - gravitational acceleration, weight will be proportional of the mass.
the mass of lorry in either case remains the same
but in case when birdies are sitting on perches, they will apply pressure to the lorry, thus their mass will add to the lorry's mass. You'll just be counting their weight combined, P = ( m1 + m2 )g
however, if you manage to launch this lorry into open space, that is, place it in vacuum, their mass will equal to m1+m2, but they will effectively weigh nothing, since g will be zero and P will be zero. I think--------
actually physics is the only school subject i've never been good at
The weight is the same if they are holding constant altitude in the lorry. For every action, etc. etc.
If they are climbing, the lorry will be heavier, since they are applying extra lift to their wings beyond their weight. If descending, the lorry is lighter.
LOL
Yes, I would say it definitely weighs less albeit a very small amount!
I suppose it would weigh the same otherwise you could put a helicopter in an enclosed container bolt it down to the bottom and it would fly with no visible mean of support.
Yes.
No.
Get a set of scales, and place a cup of water on them, when everything has settled down, put your finger in the water and see what happens.
The answers post by the user, for information only, UKQnA.com does not guarantee the right.