if it took 3.7 seconds for the sound to reach john how far away was the firework shell when it exploded in kilometers assume that the speed of sound in air is 1,236 km/h

1.2703 km

Explanation:

The speed can be calculated using the formula;

Speed (m/s) = distance (m) ÷ time (s)

Based on the information in this question, it took 3.7 seconds for a sound with speed of 1236 km/h to reach John. The distance will be:

Distance = speed × time

However, we need to convert the time in seconds (s) to hour (hr).

1 second = 0.000277778 hour

3.7 seconds = 0.00102778 hours.

Hence,

distance = 1236 × 0.00102778

Distance = 1.2703 km

where is the

the answer is the first electromagnet (a). this is because it has more coils around the ferromagnetic material. increasing the number of coils increases the surface area in which the metal interacts with the current in the coil. this enables more atoms in the metal to become aligned hence becoming more magnetized.