When I was a little girl a man across the road used to keep homing pigeons.
He told me he use to take them out into the country let them go and they would come home.
My question is, how do these birds know where home is?
Do you have a question you have always wondered about?
I've always wondered how homing pigeons find their way 'home' too. Same with cats and dogs. You move away, or they go to a new home and can still find where they were. Great Satnav eh?
Interesting question. Pigeons, like many species of animal (even some humans) have a great homing instinct. I think the jury is still out on *exactly* how they do it. Some people think that pigeons (and other species) have a way of tapping into the earth's magnetic field, so can always locate north. That's debatable, but what is quite likely is that they use the sun as a navigator. It is also very likely that they use landmarks like trees, hills, and even man made objects, like roads - just like we do in direction finding. You have to remember that birds have good eye sight and travel over long distances, so what we think is amazing is actually pretty "samey" to them.
one of the river cottage episodes Hugh wanted to move the bee hives (apiery?) but only a matter of metres, bee dude said you cant, you have to move them over 100 metres away first then move them back cos they recognise landmarks and will go back to the original hive placement if not moved far away first
When I crashed a car into my house, I SWEAR the house MOVED!!!!
Thrust and lift overcomes weight and drag.
Basically a wing is shaped so that it's upper surface is curved and longer than its flat lower surface.
As it thrusts forward, therefore overcoming it's drag the air must rush over the top half of the wing faster than the lower portion, therefore creating an area of low pressure above it and forcing the higher pressure air below to push it up.
When the amount of lift is greater than the weight the aircraft will lift from the ground.
But I'm stuffed if I know about bikes!
I guess the bike is about natural balance...
If the universe is finite but expanding as we are lead to believe then what the hell is it expanding into?
Regarding this universe malarkey ....
I've never bought into the theory about time being the fourth dimension. I know that's kicking the great Albert Einstein in the teeth, but he was pretty much guessing too, as we all are.
What the universe might be expanding into warps your mind, it's a proper brain teaser.
No one knows, but my guess is that the current ideas that the universe is approximately 13.8 billion years old and continually expanding is going to be seriously challenged quite soon. I'm not saying the universe isn't expanding, I think there is some quite clear evidence that it is. What I think will be challenged is the notion that 13.8 billion years ago there was a puff of something and the universe has been expanding even since. It may be that yes, something did happen about 13.8 billion years ago, BUT that wasn't the creation of the universe. If you accept that, then it opens the possibility that what we can currently see, or know, is just a small speck in a much greater spectrum.
Still, the Big Bang is a very media friendly topic that has made science a lot of money, so I can't see them dropping the idea very soon.