Intensity ( E ) = d V/ d R

V = potential,  r = distance

E at a point inside a spherical shell is zero.

But  V at that point is minus (-) G M by (/)R

( M- mass ,R- radius of shell )

How ?????????????Pliz explain ...............................

Positronium consists of an electron & a positron  ( same mass ,opposite charge) orbitting around their common centre of mass.

The spectrum  is therefore expected to be hydrogen like ,the difference arising from the the mass differences .

Calculate the wave number of the first line of balmer series of positronium .

I know the final answer but don't know the intermediate steps .........i wud provide it after someone tries this

1.0 gm  of  Mg atoms ( atomic mass=24 a.m.u) in the vapour phase absorbs 50 kJ of energy.Find the composition of the final mixture,if the first & second ionisation energies of Mg are 740 kJ mol^-1 & 1450 kJ mol^-1

respectively.?

Ans: i know the final solution but doesn't know the intermediate steps.........after someone tries it ,i wud provide the percentages of Mg⁺ & Mg²⁺

The derivative of a non constant even function is always  an odd

function.

If true then how & if false then how??????????

[x²] is not differentiable on (-1, 1)      ........if  true then how ........if false then how???????

 f{g(x)}=f{g(x) }=f(m),provided f is continuous at g(x)=m.

for eg:let us assume that g(x)=sgn(x)=  & f(x)= constant....

then, f{g(x)} = constanteven if g is discontinuous at x=0.....

plizzzz..... someone explain me "provided f is continuous at g(x)=m"

what is the problem if f is discontinuous?????????

i also can't understand the example.......i think its an exception to the above concept........

RATES ASSURED.........OKAYYYYYYYYY

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