On a tangent to Re: key stage two question on tv last night

> A delivery van is ferrying a consignment of live free flying budgies,
> all sitting on perches in the sealed but aeratd rear of the van. Is the
> van lighter if all the budgies are in flight? if so then surely the mpg
> will increase? as the van is now lighter, or is it? or do we care? It
> maybe a thought for all those involved in the pigeon transport world.
> Discuss...10 pts

I'd go with no... the weight of the van is actually caused by the force of
gravity acting on the masses of the van and its contents. So when the birds
take off the force lost from their weight is replaced by the downforce of
their wings (equal and opposite reaction blah blah blah) which
(theoretically) should be equal to the weight of the birds... maybe!

David

> Here's a thought. The van backfires and they all take off at exactly the
> same moment making the van over 100kgs lighter. It speeds up as a result
> of the sudden unloading and they all get killed stone dead when they get
> hit by the accelerating towards them back door. Thus dropping back to the
> floor which causes the van to slow down again due to the added dead
> weight.

I think you're thinking of flying hippo's rather than budgies... unless
they're GM budgies of course!

David

> Here's a thought. The van backfires and they all take off at exactly the
> same moment making the van over 100kgs lighter. It speeds up as a result
> of the sudden unloading and they all get killed stone dead when they get
> hit by the accelerating towards them back door. Thus dropping back to the
> floor which causes the van to slow down again due to the added dead
> weight.

I think you're thinking of flying hippo's rather than budgies... unless
they're GM budgies of course!

David

> Here's a thought. The van backfires and they all take off at exactly the
> same moment making the van over 100kgs lighter. It speeds up as a result
> of the sudden unloading and they all get killed stone dead when they get
> hit by the accelerating towards them back door. Thus dropping back to the
> floor which causes the van to slow down again due to the added dead
> weight.

I think you're thinking of flying hippo's rather than budgies... unless
they're GM budgies of course!

David

> Here's a thought. The van backfires and they all take off at exactly the
> same moment making the van over 100kgs lighter. It speeds up as a result
> of the sudden unloading and they all get killed stone dead when they get
> hit by the accelerating towards them back door. Thus dropping back to the
> floor which causes the van to slow down again due to the added dead
> weight.

I think you're thinking of flying hippo's rather than budgies... unless
they're GM budgies of course!

David

> Here's a thought. The van backfires and they all take off at exactly the
> same moment making the van over 100kgs lighter. It speeds up as a result
> of the sudden unloading and they all get killed stone dead when they get
> hit by the accelerating towards them back door. Thus dropping back to the
> floor which causes the van to slow down again due to the added dead
> weight.

I think you're thinking of flying hippo's rather than budgies... unless
they're GM budgies of course!

David

"Clive Dive" wrote ...
> "OK then, consider this
>
> A delivery van is ferrying a consignment of live free flying budgies,
> all sitting on perches in the sealed but aeratd rear of the van. Is the
> van lighter if all the budgies are in flight? if so then surely the mpg
> will increase? as the van is now lighter, or is it? or do we care? It
> maybe a thought for all those involved in the pigeon transport world.
> Discuss...10 pts

Wow, and I thought those of us over in rec.scuba had strange discussions...
<grin> Actually, our topics tend to be only about guns, politics, and sex
since we've probably discussed every diving topic to death by now...

"Clive Dive" wrote ...
> "OK then, consider this
>
> A delivery van is ferrying a consignment of live free flying budgies,
> all sitting on perches in the sealed but aeratd rear of the van. Is the
> van lighter if all the budgies are in flight? if so then surely the mpg
> will increase? as the van is now lighter, or is it? or do we care? It
> maybe a thought for all those involved in the pigeon transport world.
> Discuss...10 pts

Wow, and I thought those of us over in rec.scuba had strange discussions...
<grin> Actually, our topics tend to be only about guns, politics, and sex
since we've probably discussed every diving topic to death by now...

"Clive Dive" wrote ...
> "OK then, consider this
>
> A delivery van is ferrying a consignment of live free flying budgies,
> all sitting on perches in the sealed but aeratd rear of the van. Is the
> van lighter if all the budgies are in flight? if so then surely the mpg
> will increase? as the van is now lighter, or is it? or do we care? It
> maybe a thought for all those involved in the pigeon transport world.
> Discuss...10 pts

Wow, and I thought those of us over in rec.scuba had strange discussions...
<grin> Actually, our topics tend to be only about guns, politics, and sex
since we've probably discussed every diving topic to death by now...

"Clive Dive" wrote ...
> "OK then, consider this
>
> A delivery van is ferrying a consignment of live free flying budgies,
> all sitting on perches in the sealed but aeratd rear of the van. Is the
> van lighter if all the budgies are in flight? if so then surely the mpg
> will increase? as the van is now lighter, or is it? or do we care? It
> maybe a thought for all those involved in the pigeon transport world.
> Discuss...10 pts

Wow, and I thought those of us over in rec.scuba had strange discussions...
<grin> Actually, our topics tend to be only about guns, politics, and sex
since we've probably discussed every diving topic to death by now...