Activity

Magnifiers and sun makes fire

Summary
Burn things by focusing the sun's energy with a magnifier.
Science content
Physics: Light and Sound (1)
Physics: Energy forms, Conservation of Energy (1, 3, 4, 5)
Materials
  • safe outside space to burn stuff e.g. pavlng stones
  • the sun
  • magnifier
  • paper, dry grass, other stuff to try igniting
Procedure

Focus the sun's energy on one point with a magnifier.
Test different materials to see if they can ignite. Do not stare at the focused spot of light for long - it will hurt your eyes.
(Dried grass ignites but printer paper does not.)
The magnifier focuses the sun's energy to a point, which is hot enough to ignite things that are really thin and dry.

Notes

Try with sharpie and water lens: #2 in https://www.youtube.com/watch?v=HQx5Be9g16U start at 32 seconds.

Grades taught
Gr 3
Gr 5