At 25°c, sound can travel 100 meters across a football field in 0.29 seconds. determine the velocity of these sound waves in the direction they travel across the field.

a)
0.0029
m
s

b)
29
m
s

c)
345
m
s

d)
34,500
m
s

The correct answer is Option C.

Explanation:

Velocity is defined as the rate of change of displacement with respect to time. It is a vector quantity because it requires both magnitude and direction. It is expressed in meters/second (m/s).

Mathematically,

Where,

d = displacement = 100 meters

t = time taken = 0.29 seconds

Putting the values in above equation, we get:

The sound wave is moving with a velocity os 345 m/s in the direction of the field.

Hence, the correct answer is Option C.

5 w for 1hr = 5x60x60 joules=300x60=3000x6=18,000j as total energy conversion. efficiency of bulb needed for radiant to thermal within 18000