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What is the minimum frequency of electromagnetic radiation needed for a photon to ionise an atom of sodium? ( An atom of sodium has an ionisation energy of 5.15 eV.)

First, let's define what the ionisation energy is. The ionisation energy is the minimum amount of energy required to remove an electron from the ground state of an atom. That means, if we give an electron in...
AM
Answered by Angus M. • Physics tutor
14292 Views

Find the eigenvalues and eigenvectors of the matrix M , where M{2,2} = (1/2 2/3 ; 1/2 1/3) Hence express M in the form PDP^-1 where D is a diagonal matrix.

To start off, It's worth noting the definition of eigenvalues: for a Matrix A (n x n), it's ith eigenvalue (λ i ) is defined as the scalar constant the ith eigenvector (v i ) is multiplied for the matrix mul...
LT
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Find dy/dx in terms of t for the curve given by the parametric equations x = tan(t) , y = sec(t) for -pi/2<t<pi/2.

We know that dy/dx = (dy/dt) * (dt/dx). Differentiating each of the equations with respect to t gives. dy/dt = sec(t) tan(t) and dx/dt = sec 2 (t). Since dt/dx = 1 / (dx/dt) we have that dt/dx = 1/(sec 2 (t)...
OC
Answered by Oliver C. • Maths tutor
6949 Views

7x+5y-3z =16, 3x-5y+2z=-8, 5x+3y-7z=0. Solve for x,y and z.

There are three methods to solve these types of silmultaneous equation questions, substitutution, elimination and matrices. In this example we use substitution and elimination.Elimination example.Eq1). 7x+5y...
HM
Answered by Holly May B. • Maths tutor
9781 Views

Explain the difference between the Irenaeus and Augustine theodicies (solution to the problem of the evil)?

Their understandings of natural evil is what differtentaites the Irenaeus and Augustine theodicies. Irenaeus believes that natural evil is necessary in the world so that we as humans have something to overco...
LG
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