The green house effect does help keep earth warm enough for people to live on & increases the temperature.
Increased gas emissions isn’t necessarily a natural process since it’s due to the burning of fossil fuels, deforestation, etc.
Without the greenhouse effect earth would be uninhabitable and cold as heck because without greenhouse gasses no heat would be trapped and held in the atmosphere.
"<span>The number of times a machine multiplies the effort force is the what of the machine"
Work Output is the answer, I believe.</span>
Answer:
8.6 m/s
Explanation:
The observer is stationary
The source is moving
Let v₀ be the speed of sound in the air
Let v be the speed of the ambulance
As the siren approaches
f₁ = 2000(v₀ / (v₀ - v))
As the siren departs
f₁' = 2000(v₀ / (v₀ + v))
f₁ - f₁' = 100
2000(v₀ / (v₀ - v)) - 2000(v₀ / (v₀ + v)) = 100
v₀ / (v₀ - v) - v₀ / (v₀ + v) = 100/2000
v₀(v₀ + v) / (v₀ - v)(v₀ + v) - v₀(v₀ - v) / (v₀ - v)(v₀ + v) = 0.05
(v₀² + vv₀) - (v₀² - vv₀) / (v₀² - v²) = 0.05
2vv₀ / (v₀² - v²) = 0.05
2vv₀ = 0.05 (v₀² - v²)
0.05v² + 2vv₀ - 0.05v₀² = 0
v² + 40vv₀ - v₀² = 0
quadratic formula positive answer
v = (-40v₀ + √((40v₀)² - 4(1)(v₀²))) / 2
v = (-40v₀ + √(1604v₀²)) / 2
v = (0.049968v₀) / 2
v = 0.02498439v₀
If we assume the speed of sound in air is 343 m/s
v = 8.56964... = 8.6 m/s
Approaching frequency heard is 2051 Hz
Departing frequency heard is 1951 Hz