Question

Speed of Light in vacuum is :

• A. $3 \times 10^6$ m/s
• B. $3 \times 10^8$ m/s
• C. $3 \times 10^5$ m/s
• D. $3 \times 10^7$ m/s

Hint:

A common mistake is choosing $3 \times 10^5 \text{ km/s}$. While that value is correct in kilometers, always check the units. In meters per second (m/s), which is the SI standard, the exponent must be $10^8$.

Answer 1

The Correct Option is B