Activity 16.7 Class 8 Science Chapter 16 Solution

we will go through activity 16.7 class 8 science chapter 16 Light in which we will discuss splitting of white light into seven colours. You should also go through activity 16.4 to get more about reflection.

Activity

·     Get a plane mirror of a suitable size.

·     Place it in a bowl (katori) as shown in the figure below.

·     Fill the bowl with water.

·     Put this arrangement near a window in such a way that direct sunlight falls on the mirror.

·     Adjust the position of the bowl so that the reflected light from the mirror falls on a wall.

·      If the wall is not white, fix a sheet of white paper on it.

·     Reflected light will be seen to have many colours.

·     How can you explain this?

·     The mirror and water form a prism.

·      As you learnt in Class VII, this breaks up the light into its colours, splitting of light into its colours is known as dispersion of light.

·     Rainbow is a natural phenomenon showing dispersion.

 Activity 16.7 Class 8 Science Chapter 16 Solution

Observation and explanation

When the sunlight falls on the ‘arrangement’ we have placed near the window, the sunlight gets reflected and falls on the white wall. We can see different colours on the wall.

This phenomenon of splitting of white light into colours is called ‘dispersion of light’.

This happens because water and mirror form a prism that splits light into seven colours. The band of seven colours is known as the spectrum.

In nature, a rainbow (VIBGYOR)is formed at the time of rain when the sunlight passes through water droplets and splits into seven colours(rainbow) due to total internal reflection and refraction.

Conclusion

Sunlight is white light that consists of seven colours. The splitting of light into seven colours is known as dispersion.

Related Topics

1Activity 16.8

2. Activity 16.6