Question

What is the time taken by the light to travel from the Sun to the Earth?

• A. 10 minutes
• B. 15 minutes
• C. 8 minutes
• D. 3 minutes

Answer 1

Answer: (C)

1. It is known, that the distance between the sun and the earth is $\text{149,600,000km}$ which is approximately taken as $15\times {10}^{7}km=15\times {10}^{10}m$
2. ​The speed of light is taken as $3\times {10}^{8}m{s}^{-1}$.
3. Now, we know that, $time=\frac{Distance}{speed}$ , thus,

The time taken by the sunlight to reach to the earth is;

$t=\frac{15\times {10}^{10}m}{3\times {10}^{8}m{s}^{-1}}$

$t=5\times {10}^{2}s$

$t=500s$

$t=\frac{500}{60}minutes$

$t\simeq 8minutes$

Thus,

Option A) $8minutes$ is the correct option.