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# Clarification over formulas. watch

1. Are "Magnifying power" and "Angular Magnification" the same thing?

Because I have 2 formulas:

Magnifiying Power = 1/f = 1/(focal length) = 1/(f nought)

Angular Magnification = Angle...eye/Angle...object = Focal Length/fe = (f nought)/fe

1.) Are these 2 formulas correct?
2.) Are MP and M the same thing? (My original Q)
3.) If not, what are the units of each? If yes, is the unit Diopters?

Cheers
2. 1. yes
2. M=fo /fe = beta/alpha

where:
beta = angle of resultant ray after eyepiece
alpha = angle of incidence to plane of lens at entry side of objective

3. Yes. Diopters (D)
3. Oh hell forgot to add - M=1/f is true for a single lens on it's own. M=fo /fe is true for an refracting telescope where:

fo = focal length of objective lens
fe = focal length of eyepiece lens

The refracting telescope image is inverted, diminished, and at infinity.
4. No worries. Take it you're doing module 5 tomorrow. All the best.
But dont do so well you push the grade boundaries out of my reach!

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