The highest refractive index is of :

Options

A. glass
B. water
C. diamond
D. ruby

Answer

To determine which material has the highest refractive index among the given options, we can follow these steps:

### Step 1: Understand the concept of refractive index
The refractive index (n) of a medium is defined as the ratio of the speed of light in vacuum to the speed of light in that medium. It indicates how much light bends when entering a material.

### Step 2: List the refractive indices of the given materials
- Glass: n = 1.5
- Water: n = 1.33
- Diamond: n = 2.42
- Ruby: n = 1.77

### Step 3: Compare the refractive indices
Now we will compare the refractive indices of the materials listed:
- Glass (1.5)
- Water (1.33)
- Diamond (2.42)
- Ruby (1.77)

### Step 4: Identify the highest refractive index
From the comparison, we can see that:
- 1.5 (Glass) < 1.77 (Ruby) < 1.33 (Water) < 2.42 (Diamond)

### Conclusion
The highest refractive index among the options provided is that of diamond, which is 2.42. Therefore, the answer is **diamond**.

### Final Answer
The highest refractive index is of **diamond**.

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