You need to use Planck's law:
E = h·υ = (h·c)/λ
Without making all the calculations, a fraction is bigger than another when the denominator is smaller. Therefore you need to find the smallest wavelength (λ) which is 450nm.
You could also be helped by colors: in order of decreasing energy, you have blue - green - yellow - red.
In any case, the correct answer is a).
Answer:
1497×10⁵ km
Explanation:
Speed of light in vacuum = 3×10⁵ km/s
Time taken by the light of the Sun to reach the Earth = 8 min and 19 s
Converting to seconds we get
8×60+19 = 499 seconds
Distance = Speed × Time
1 AU = 1497×10⁵ km
The Sun is 1497×10⁵ km from Earth
Seafloor spreading<span> is a process that </span>occurs<span> at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. </span>Seafloor spreading<span> helps explain continental drift in the theory of plate tectonics.
Hope this helps</span>
Answer:
r = 5,085 m
Explanation:
The force exerted by on the surface of the Earth on an electron is its weight
W = F = 9.11 10⁻³¹ 9.8
W = 8.9 10⁻³⁰ N
The electric force between an electron and a proton is given by Coulomb's Law
Fe = k q₁ q₂ / r²
Fe = - k q² / r²
They ask us that W = Fe
W = k q² / r²
r = √ k q² / W
Let's calculate
r = √ 8.99 10⁹ (1.6 10⁻¹⁹)² /8.9 10⁻³⁰
r = √ 25.86
r = 5,085 m
Let's look for the relationship of this distance with the harmonic distance
R / R_atomic = 5,085 / 10⁻¹⁰
R / R_Atomic = 5 10¹⁰
We see that this distance is 10¹⁰ times the interatomic distance, so the gravitational attraction force is very small at atomic scale
