Table of Contents
Activity 14.5 NCERT Class 10 Science, Sources of Energy
Brief procedure:
Activity 14.5 wants us to show that black painted objects absorb more heat. For this, it asks us to bring two beakers, one painted with black and another without paint.
Water in the black painted beaker is hotter than the water in a non-painted beaker.
Explanation:
Every object absorbs light rays and emits some wavelength. We see the colour of the object because it emits rays. For example, a green tennis ball absorbs all colour and emits the wavelength of green colour. A black colour object absorbs all the light rays and does not emit any colour. Due to this, we feel the object is black. A black painted beaker absorbs all rays of sunlight. The energy of sunlight rays makes the water in weaker warm.
Application:
Solar Cooker: A solar cooker is coated with black paint. It absorbs solar rays and uses it to heat the food.
Wall paint: We usually paint outer water of home with light colour. It reflects more light and the house remains cooler than surrounding.
Next: Design of a solar cooker, its advantages and disadvantages. Activity 14.6.
Previous: Comparision of our living with older days. Activity 14.4.
Thank you very much this helped me a lot for my seminar.