Burning a paper with sun rays in Combustion, Fuels and Flames – Class 8 Science Experiment
Chapter Name: Combustion, Fuels and Flames
Activity Name: Burning a paper with sun rays in Combustion, Fuels and Flames
Activity Description:
In this experiment, we will use a magnifying lens to focus the sun’s rays on a piece of paper. The goal is to observe the paper catching fire due to the concentrated heat from the sunlight. We will also compare this with ancient methods of generating sparks by rubbing stones together.
Required Items:
- Magnifying lens
- Piece of paper
- Sunny day
Step by Step Procedure:
- Choose a sunny day to conduct the experiment.
- Go outdoors and position yourself under direct sunlight.
- Place the piece of paper on a flat surface in the sunlight.
- Hold the magnifying lens between the paper and the sun, adjusting the angle until the sun’s rays converge onto a small spot on the paper.
- Observe the paper carefully for any signs of ignition or burning.
- After some time, touch the spot where the sun’s rays were focused and note your observations.
Experiment Observations:
- The focused sunlight on the paper causes it to catch fire and burn.
- When rubbing the two stones together, there may be some friction-generated heat, but they may not produce sparks as readily as modern tools.
Precautions:
- Be cautious while using the magnifying lens under direct sunlight to avoid accidental exposure to the intense light.
- Conduct the experiment in an open and safe area away from flammable materials.
Lesson Learnt from Experiment:
The experiment demonstrates that a combustible substance, such as paper, requires an initial heat source to catch fire or burn. In this case, the sun’s concentrated rays provide the necessary heat to ignite the paper. Similarly, in ancient times, rubbing stones together could create enough heat to potentially ignite certain materials, leading to the discovery of fire-making techniques.
