Answer:
Explanation:
18 kW = 18000 J /s
60% of 18kW = 10800 J/s
Latent heat of evaporation of water
= 2260 x 10³ J / kg
kg of water being evaporated per second
= 10800 / 2260 x 10³ kg /s
= 4.7787 x 10⁻³ kg / s
= 4.78 gm / s .
Answer: Saving is important to the economic progress of a country because of its relation to investment. If there is to be an increase in productive wealth, some individuals must be willing to abstain from consuming their entire income.
Explanation:
Answer:
in oil film λ = 303.57 10⁻⁹ m
in the water film λ = 319.55 10⁻⁹ m
Explanation:
When electromagnetic radiation reaches a material, its propagation is by a process that we call absorption and reflection,
when light reaches a surface it has a mass much greater than the mass of the photons (m = 0), therefore there is an elastic collision where the frequency does not change, due to the speed of light in the material medium changes, therefore the only possibility is that the wavelength in the material changes, to maintain the relationship
v = λ f
in the void we have
c = λ₀ f
we divide the two expression
c / v = λ₀ / λ
the refractive index is
n = c / v
n = λ₀ /λ
λ = λ₀ / n
let's calculate
in oil film
λ = 425 10⁻⁹ / 1.40
λ = 303.57 10⁻⁹ m
in the water film
λ = 425 10⁻⁹ / 1.33
λ = 319.55 10⁻⁹
those wavelengths are in the ultraviolet
Define and measure the speed
choose this
heliocentric theory = Ptolomeu
radioactivity = Becquerel
reflecting telescope - Newton (not sure)