Question

Kabaddi players rub their hands with soil so that they can:
A. Make their skin dry
B. Moisture the hands
C. Get a better grip while holding the opponent
D. Soil the opponent

Answer 1

Hint: Soil makes the hands rough. Frictional force depends on two quantities – frictional coefficient and normal force of the surface. You can increase the frictional force by increasing the frictional coefficient of the surfaces. Frictional coefficient depends on the roughness of the surfaces.

Formula Used:
The frictional force is given by,
$F=\mu N$

Where,
$\mu $ is the frictional coefficient
$N$ is the normal force on the object.

Complete step by step answer:
Let us first understand how frictional force works before answering this question.
We can understand the following diagram:

So, the frictional force is given by,
$F=\mu N$

The term μ is called the frictional coefficient.

It depends on the surface of the two objects. If the roughness of the surfaces is more, then μ will be more.

So, for the same normal force, we will get more frictional force.

Kabaddi players want to have a firm grip on the opponent’s body. Smooth hand has a lower value of μ. As a result, the grip is not firm.

However, if the Kabaddi player puts some dirt on the hands, it will increase the roughness.

It increases the μ of the surface. So, the player can grab the other player more firmly.

This is why Kabaddi players often put dirt on their hands.
Hence, the correct answer is - (C).

Note: The frictional force is useful in a lot of cases. The operation principle of the cycle also depends on friction. A cycle is able to move because of the frictional force. Also, you can hold an object on the wall more easily if the wall is rough. It is harder to hold an object vertically if the wall is smooth or oily.