Concepts of Physics

IIT JEE Physics (1978-2018: 41 Years) Topic-wise Complete Solutions

Cotton Fiber as Capillary

Objective

To see capillary action

Introduction

Materials made up to fibers acts as narrow capillary tube.

Apparatus

cotton or jute string, glasses of water

Procedure

Place a glass full of water at a height of 1-2 inch. Place the other empty glass at lower level. Wet the cotton or jute string. Dip one of its end in the glass with water and leave the other end in the empty glass. Leave the setup undisturbed. After a few hours, you will find that most of the water has collected into the lower glass.

Discussion>

Water rises up the string due to the capillary action. Once water crosses the rim of the upper glass, gravity makes it to move downward. This process continues till water gets transferred from one glass to another.