Question

25. One day reeta went to a jeweller's shop with her mother. Her mother gave old gold jewellery to the
goldsmith to polish. Next day when they brought the jewellery back they tound that there was a slight loss
in its weight. Can you suggest a reason for the loss in weight?
3
Ro, You might has observed that porter place or their heads a round piece of cloth, when they have to
U sarry heavy loads. Witails the reason behind this?
S A boy talis down when he steps on a banana peel. Same thing is coserved on a smooth and wet oor. Can
By you find answers to such observations?​

Answer 1

Answer:

For the first one, it's because of polishing... The upper layer of gold is scraped off so that the shiny layer underneath is revealed

Answer 2

Explanation:

• To polish a gold ornament it is dipped in a liquid called aqua regia (a mixture of hydrochloric acid and nitric acid) on getting the environment of the aqua regia the outer layer of gold is dissolved and the inner shiny layer appears the dissolving of the layer causes a reduction of weight of the jewellery.

• porters place a round piece of cloth on their head when they carry heavy lods as the round piece of cloth increases the area on which the load is placed. We know that when surface is more than pressure is less. As a result, the pressure on their heads get reduced.
• We slip when we step on a banana peel because the inner side of banana peel being smooth and slippery reduces the friction between the sole of our shoe and the surface of road.

hope this will help. please mark brainliest :)