Q13 of 17 Page 236

Kumaran went to a shop near his house on a bicycle. The bicycle made a lot of noise when he pedalled it. After coming home, he applied some oil on some parts of the bicycle. Then there was no noise, why?

The cycle was making a lot of noise due to friction between its different parts. As oil is a lubricator, it lubricates the surfaces and reduces friction which in turn reduces the noise.


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