This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
In reality, there is a lot of air on top of the cotton bag.  The atmospheric pressure is 1 atm = 10⁵ Newtons / m².

If the surface area of the cotton bag is 4 meter square, then the weight of air column on top of the cotton bag = 10⁵ * 4 = 400, 000 kg.

If the platform of the weighting machine and iron bar is  3 m², then the weight due to air column on weighing machine, when the iron bar is placed = 3 * 10^5 kg.

Thus the reading is more when the cotton bag is placed on the weighing machine.

1 5 1