Change in distance and view object in Human Eye and Colourful World – Class 10 Science Experiment
Chapter Name: Human Eye and Colourful World
Activity Name: Change in distance and view object in Human Eye and Colourful World
Activity Description:
This experiment aims to investigate how the ability to see both ends of an object simultaneously without shaking the eyes depends on the distance of the object from the observer’s eyes.
Different lengths of wooden sticks or PVC pipes are used as objects, and their positions are adjusted at a fixed distance from the observer’s eyes to observe the effects on vision.
Required Items:
- Wooden sticks or PVC pipes (20 cm, 30 cm, 35 cm, 40 cm, 50 cm)
- Retort stand
- Clamp
- Table
Step by Step Procedure:
- Set up the retort stand on a table and stand next to it, ensuring that your head is beside the vertical stand.
- Adjust the clamp on the horizontal rod and fix it at a distance of 25 cm from your eyes.
- Ask a friend to fix a wooden stick of 30 cm height to the clamp in a vertical position.
- Keep your vision parallel to the horizontal rod and try to see the top and bottom of the wooden stick without any shaking of the eyes.
- If you cannot see both ends of the stick at the 25 cm distance, adjust the vertical stick on the horizontal rod until you can see both ends clearly.
- Fix the vertical stick at this position with the help of the clamp.
- Without changing the position of the clamp on the horizontal rod, replace the 30 cm stick with other sticks of various lengths (20 cm, 35 cm, 40 cm, 50 cm) one by one.
- Try to see the top and bottom of each stick simultaneously without any change in the position of your eyes either upwards, downwards, or sideways.
Experiment Observations:
- Note whether you can see both ends of the sticks without any movement or shaking of your eyes.
- Record the distance at which each stick is fixed to the clamp to achieve distinct vision.
Precautions:
- Handle the wooden sticks or PVC pipes carefully to avoid any injuries.
- Ensure the retort stand is stable and securely placed on the table.
- Avoid looking directly at the sun or a bright light source during the experiment.
Lesson Learnt from Experiment:
The ability to see both ends of an object simultaneously without shaking the eyes depends on the distance of the object from the observer’s eyes. The least distance for distinct vision can vary from person to person.
