Question

If the Sun suddenly turned off, we would not know it until its light stopped coming. How long would that be, given that the Sun is$1.50\times {10}^{11}$away?

Short answer

The time taken is 500 s or 8.33 min .

Step-by-step solution

Define distance-time theory.

Distance-time theory defines distance as equivalent to a time period according to the equation D= ct.

Given information and Formula to be used

The speed of the light is$c=3\times {10}^{8}m/s$

The distance between Sun and the earth$d=1.50\times {10}^{11}m$

The relation between distance and speed of light can be expressed as,

$d=c\times t$……………(1)

How long does it take light to stop coming if Sun suddenly turned off, given that the Sun is 1.50×1011m away?

Rearrange the equation (1) for t and substitute the given data, such that,

$$\begin{gathered} t=\frac{1.50\times {10}^{11}m}{3\times {10}^{8}m/s} \\ =500s\left(\frac{1min}{60s}\right) \\ =8.33min \end{gathered}$$

Therefore, the time taken is 500 s or 8.33 min.