Question

Why do we hear thunder seconds after a lightning strike ?

Answer 1

Answer:

In context of Physics, Thunder is Sound, and Lightning is Light. Read the explanation to understand.

Explanation:

It is because the speed of light (i.e. 300000000 m/s) is faster than the speed of sound (i.e. 330 m/s). Let me give you an example, the cloud is 8 km away :

$Time(ForLight)=\frac{8000m}{300000000m/s}$

$Time(ForLight)=2.66sec$

$Time(ForSound)=\frac{8000m}{330m/s}$

$Time(ForSound)=24.24sec$

Time Difference = Time(For Sound)-Time(For Light)

Time Difference = (24.24-2.66)sec

Time Difference = 21.58sec

Time Difference =22sec approx.

Here by this example where the time difference is approximately 22 seconds, you can understand why the time difference exists.