Refraction and Snell's law

Answer Key - Grade 11 Science Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. 1.

   Use n = 1.00 for air. What is the critical angle for light inside water (n = 1.333) meeting a surface with air, to 0.1°, Ari?

   48.6 °
2. 2.

   Use n = 1.00 for air. What is the critical angle for light inside diamond (n = 2.417) meeting a surface with air, to 0.1°, Bo?

   24.4 °
3. 3.

   Use n = 1.00 for air. What is the critical angle for light inside Plexiglas (n = 1.49) meeting a surface with air, to 0.1°, Esme?

   42.2 °
4. 4.

   How does an optical fiber carry light around a gentle bend, Kira?

   • Total internal reflection at its walls
   • Light bends smoothly to follow the fiber's curve
   • The fiber glows on its own
5. 5.

   Milo says light entering water from air bends away from the normal. Agree or disagree?

   • Disagree: it bends toward the normal
   • Agree: slower light bends away
   • Agree: water pushes light away
6. 6.

   Noah says a ray entering diamond from air bends away from the normal because diamond is so hard. Agree or disagree?

   • Agree: diamond speeds light up
   • Disagree: it bends toward the normal
   • Agree: hard materials push light away
7. 7.

   Pia says light going from air into water can be totally internally reflected. Agree or disagree?

   • Agree: any boundary can do it
   • Disagree: it needs a higher index to a lower one
   • Agree: water reflects light that way
8. 8.

   A material has an index of exactly 1.00, like a vacuum. How would a ray from a vacuum bend entering it, Ren?

   • Not at all
   • Away from the normal
   • Toward the normal
9. 9.

   Rays from air enter water and diamond at the same angle. In which is the ray closer to the normal, Tala?

   • They are the same
   • Diamond
   • Water
10. 10.

    How does a material's critical angle change as its index gets bigger, Zee?

    • It gets bigger
    • It gets smaller
    • It stays at 90°