engineering recuitment NPCIL Scientific Assistant Physics Mock Test Physics Optics Refraction and Reflection
If the critical angle for total internal reflection from a medium to vacuum is 30∘. Then the speed of light in the medium is
1
6 × 108 m/s
2
3 × 108 m/s
3
2 × 108 m/s
4
1.5 × 108 m/s