question_answer

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?

Answer:

                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 becomes heavier, when bird flies upwards with an acceleration. (iii) the cage appears lighter, when bird flies downwards with an acceleration.