NEET Physics Question - Laws of Motion

Assertion (A): An air tight cage in which a bird is sitting, is suspended from a spring balance. If the bird starts flying upwards with some acceleration, then the reading of the balance will increase.

Reason (R): The weighing machine measures the actual weight of a body.

(1) Both (A) & (R) are true and the (R) is the correct explanation of the (A)

(2) Both (A) & (R) are true but the (R) is not the correct explanation of the (A)

(3) (A) is true but (R) is false

(4) Both (A) and (R) are false

Solution:

When the bird flies up with acceleration, it pushes more air downwards, increasing the effective weight measured. So (A) is true. A weighing machine measures apparent weight, not always actual weight. Thus (R) is false.

Rankers Physics

Bird in Spring Balance

Solution:

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