Answer:
Mass, m = 19466.7 kg
Explanation:
Given that,
Portland cement concrete (PCC) has a density of 150 lb/ft³
We need to find how many kilograms of PCC are required to cast a cylindrical column 1.15 m in diameter and 7.8 m in height.
Since, 1 kg = 2.205 lb
1 lb/ft³ = 16.018 kg/m³
150 lb/ft³ = 2402.77 kg/m³
Density,
m is mass of PCC in kg and V is volume of cylinder
So, the mass of PCC required is 19466.7 kg.
Si nunez y adolécenos reconcile la capitaliza
When an alpha particle is emitted from a nucleus the nucleus loses two protons and two neutrons. This means the atomic mass number decreases by 4 and the atomic number decreases by 2. The electron is ejected from the nucleus and is called the beta particle. The proton stays in the nucleus and changes the identity of the atom, to the next higher atomic number.
Answer:
λ=2167.6 nm
The wavelength of light emitted is 2167.6 nm.
Explanation:
We recall that Eₙ=
since there was transition from n7 to n=4 we will first calculate the change in the energy i.e ΔE
ΔE=E₄-E₇
ΔE=
ΔE=-9.1760*10^-20 J
Now:
|ΔE|=Energy of photon=h*v=h*c/λ
λ=h*c/|ΔE|
λ=
λ=2.1676*10^-6 m
λ=2167.6*10^-9 m
λ=2167.6 nm
The wavelength of light emitted is 2167.6 nm.