A bird is sitting on the floor of a closed glass cage and the cage is in the hand of a girl. Will the girl experience any change in the weight of the cage when the bird (i) starts flying in the cage with a constant velocity (ii) flies upwards with acceleration (iii) flies downwards with acceleration ?

Explanation

In a closed glass cage , air inside is bound with the cage . Therefore . (i) there would be no change in weight of the cage if the bird flies with a constant velocity . (ii) the cage becomses heavier , when bird flies upwards with an accelertion . (iii) the cage appears lighter when bird flies downwards with an acceleration .