Weight Reading
A bird in a cage. What happens to the weight when it starts flying?
There is a bird in a cage.
The cage with the bird standing in it is placed on a set of scales.
The bird now starts flying around in the cage.
What happens to the weight reading and why?
And would it make a difference if the cage was barred or completely closed?
That's an interesting question.
When the bird is not flying, the scale would register the weight of the cage and the weight of the bird.
Now when the bird flies, while still inside the cage, the air "lift" produced by the wings of the bird sustains the weight of the bird. The floor of the cage does not bear anymore the weight of the bird.
This argument holds through even on other cases. Now consider, if an airplane flies directly overhead, will we feel its weight?
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