How far away is a lightning strike if you hear the thunderclap 2.00 s after you see the lightning bolt strike? (v_sound = 340 m/s,v_light = 3 × 10⁸ m/s) A) 113 m B) 340 m C) 680 m D) 1020 m

Question

Quizplus · Accepted Answer

To solve the problem, we need to use the fact that sound travels at a constant speed of 340 m/s, while light travels at a much faster speed of 3 x 10^8 m/s. We can use the equation:

distance = speed x time

First, we use the time it took for the sound to travel (2.00 s) to find the distance it traveled from the lightning strike to our location:

distance_sound = speed_sound x time = 340 m/s x 2.00 s = 680 m

Next, we use the time it took for the light to reach our location (which is essentially 0, since light travels so fast) to find the distance it traveled:

distance_light = speed_light x time = 3 x 10^8 m/s x 0 s = 0 m

Finally, we can subtract the distance the sound traveled from the distance the light traveled to find the total distance to the lightning strike:

total_distance = distance_light - distance_sound = 0 m - 680 m = -680 m

Since the answer is negative, it means that the lightning strike was behind us, so we need to reverse the direction and take the absolute value of the answer:

total_distance = | -680 m | = 680 m

Therefore, the lightning strike was 680 m away, or choice C.

How Far Away Is a Lightning Strike If You Hear