Planck's equation states that
E = hf
where
E = the energy,
h = Planck's constant
f = the frequency
Because
c = fλ
where
c = velocity of light,
λ = wavelength
therefore
E = h(c/λ)
Photon #1:
The wavelength is λ₁ = 60 nm.
The energy is
E₁ = (hc)/λ₁
Photon #2:
The energy is twice that of photon #1, therefore its energy is
E₂ = 2E₁ = (hc)/λ₂.
Therefore
Answer: 30 nm
"Nuclear Fusion" <span>produces radiant energy in stars
Hope this helps!</span>
Answer:
1.324 × 10⁷ m
Explanation:
The centripetal acceleration, a at that height above the earth equal the acceleration due to gravity, g' at that height, h.
Let R be the radius of the orbit where R = RE + h, RE = radius of earth = 6.4 × 10⁶ m.
We know a = Rω² and g' = GME/R² where ω = angular speed = 2π/T where T = period of rotation = 1 day = 8.64 × 10⁴s (since the shuttle's period is synchronized with that of the Earth's rotation), G = gravitational constant = 6.67 × 10⁻¹¹ Nm²/kg², ME = mass of earth = 6 × 10²⁴ kg. Since a = g', we have
Rω² = GME/R²
R(2π/T)² = GME/R²
R³ = GME(T/2π)²
R = ∛(GME)(T/2π)²
RE + h = ∛(GMET²/4π²)
h = ∛(GMET²/4π²) - RE
substituting the values of the variables, we have
h = ∛(6.67 × 10⁻¹¹ Nm²/kg² × 6 × 10²⁴ kg × (8.64 × 10⁴s)²/4π²) - 6.4 × 10⁶ m
h = ∛(2,987,477 × 10²⁰/4π² Nm²s²/kg) - 6.4 × 10⁶ m
h = ∛75.67 × 10²⁰ m³ - 6.4 × 10⁶ m
h = ∛(7567 × 10¹⁸ m³) - 6.4 × 10⁶ m
h = 19.64 × 10⁶ m - 6.4 × 10⁶ m
h = 13.24 × 10⁶ m
h = 1.324 × 10⁷ m
Answer:
Explanation:
I = V/R = 120 V/ 50 Ω = 2.4 A
P = VI = 120(2.4) = 288 W = 288 J/s
288 J/s (15 min(60s / min)) = 259,200 J
or the electric company would charge for
288 W / (1000 W/kW)•(15/60) hr = 0.072 kW•hr
At $0.20 / kW•hr, that would be under 1½ cents
