Answer:
37.545 m/s
Explanation:
f' = Actual frequency of horn = 269 Hz
f = Observed frequency of horn = 290 Hz
v = Speed of sound in air = 343 m/s
= Speed of second train = 13.7 m/s
= Speed of first train
From Doppler effect we have
The speed of the first train is 37.545 m/s
The smallest level of organization in living things is the atom.
Next in line would be the cell, since a cell is made up of atoms working together. Next, cells working together would make up a tissue, and further, tissues working together would make up an organ.
Answer:
<em>Aim at the base of the fire and use short bursts until the fire is out.</em>
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Explanation:
Fire extinguishers use CO2 (Carbondioxide) as the extinguishing agent. This is because CO2 is denser than air, and does not support combustion.
Aiming at the base of the fire causes the CO2 to fall on the base of the fire, where the source of the fire is, trapping it, and preventing it from further reacting with air in a combustion reaction. Also, the short burst creates a strong wind that forces the flame to blow out.
The correct answer is<span> number of oscillations in a given period of time
This is measured in what is called the Hertz measurement and the period of time is usually taken to be per second.</span>
