Question 43

The speed of light in water is greater than 0 but less than 300,000 km/s.

In water, light travels slower than in a vacuum, which means its speed is greater than 0 but less than 300,000 km/s, confirming that the correct option is B.

A) greater than 0 but less than 300,000 km/s

This option is correct because in a medium like water, the speed of light is reduced compared to its speed in a vacuum, affirming that it is indeed greater than 0 but less than 300,000 km/s.

B) 300,000 km/s

This option is incorrect because the speed of light in a vacuum is 300,000 km/s, and in any other medium, including water, it is always less than this value.

C) greater than 300,000 km/s

This option is incorrect because it contradicts the fundamental principle that light slows down when it enters a medium, meaning it cannot exceed the speed of light in a vacuum.

D) greater than 300,000 km/s

This option is incorrect as it falsely implies that light can travel faster than its maximum speed in a vacuum, which is not possible according to the laws of physics.

Conclusion

The correct answer, B, accurately reflects the behavior of light as it moves through water, where it is indeed slower than in a vacuum. All other options fail because they either misrepresent the speed of light in different mediums or incorrectly state that the speed can exceed its known maximum in a vacuum.