Answer:
The correct option is;
Light energy, which shines on the area around the fire
Explanation:
From the given figure the flame is visible, as the translucent region which shows that the heat from the fire causes flammable organic (carbon containing) vapors to rise and as the vapors get ignited to burn, the heated carbon atoms including the other atoms present in the burning vapor emit light energy due to their incandescent (emitting light when heated) nature, in the same manner an incandescent electric bulb produces light.
Light energy is the visible form of electromagnetic radiation that consists of packets of electromagnetic energy called photons which are emitted by the atoms of a heated incandescent material.
Answer:
False
Explanation:
The time rate of flow of electric current is not the charge. Electric current is the time rate of flow of electric charge.
Its unit is in Amperes;
Electric current =
Therefore, it wrong to say charge is the quantity of electric current that flows per unit of time.
Charge is the amount of electrons within an atom
Momentum is the product of mass and velocity.
Thus, P=mv
where,
P is momentum.m is mass of the body.v is velocity of the body.
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