Across
- 3. measure of how strong the light is
- 6. dark shapes formed when light is stopped
- 7. prevented from passing through by something
- 8. plural of line used to show light paths
- 10. in an undeviating direction
- 11. degree of light emitted or seen
Down
- 1. a thing that can be seen or touched
- 2. not giving much light; faintly lit
- 3. very strong in force or feeling
- 4. moves from one place to another
- 5. ability to do work or produce effect
- 7. giving a lot of light; shining strongly
- 9. long, thin beams of light