The deepest section of ocean in the world is the Mariana Trench, located in the Pacific Ocean. Here the ocean floor is as low as 10,918m below the surface. If the index of refraction of water is 1.33, how long would it take a laser beam to reach the bottom of the trench?

I will be happy to critique your thinking.

.0000484s

To calculate the time it would take for a laser beam to reach the bottom of the Mariana Trench, we need to know the speed of light in water. The speed of light in a medium is given by the equation:

Speed of light in a medium = Speed of light in a vacuum / Index of refraction

Given that the index of refraction of water is 1.33, we can calculate the speed of light in water by dividing the speed of light in a vacuum (which is approximately 3 x 10^8 meters per second) by 1.33:

Speed of light in water = (3 x 10^8 m/s) / 1.33

Now we can calculate the time it would take for the laser beam to cover the distance from the surface to the bottom of the Mariana Trench.

Distance to be covered = 10,918 meters
Time = Distance / Speed

Substituting the values:

Time = 10,918 meters / Speed of light in water

Now, we can plug in the value we calculated for the speed of light in water:

Time = 10,918 meters / (3 x 10^8 m/s) / 1.33

Simplifying:

Time = 10,918 meters / (3 x 10^8 m/s) * 1.33

Calculating the final result:

Time ≈ 0.03866 seconds

Therefore, it would take approximately 0.03866 seconds for a laser beam to reach the bottom of the Mariana Trench.