Newton's formula

An expression relating the focal lengths of an optical system (f and f′) and the object x and image x′ distances measured from the respective focal points. Thus,

ff′ = xx′

If the optical system is a lens in air −f = f′ and the formula becomes

−f² = xx′

Syn. Newton's equation; Newton's relation. See fundamental paraxial equation; sign convention; gaussian theory.

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References in periodicals archive ?

The images gave a value of 0.86 for the deflection, about in line with Newton's formula, but with large uncertainties.

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Hu Ning according to general relativity and Binet's formula, we get the following improved Newton's formula of universal gravitation

[3] Fu Yuhua, Improved Newton's formula of universal gravitation, Ziranzazhi (Nature Journal), 2001(1), 58-59

An example of guiding scientific research with philosophical principles based on uniqueness of truth and neutrosophy deriving Newton's second law and the like

3 With the help of general relativity and accurate experimental data to derive the improved Newton's formula of universal gravitation

Hu Ning derived an equation according to general relativity, with the help of Hu's equation and Binet's formula, we get the following improved Newton's formula of universal gravitation[2]

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By applying Newton's formula, a planet's future path can be told from its present position and velocity and all the gravitational pulls that it experiences.

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There are the two following analogues of Newton's formula (3.1):

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YOU CAN CALCULATE recoil kinetic energy with Sir Isaac Newton's formula: KE = M[V.sup.2]/ GC, where M is a rifle's mass and V is velocity.

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It's about as scientific as reading monkey bones, but some minds don't buy Newton's formula wholesale.

STICKBOW

In particular, the unified field theories say that the force of attraction between two bodies is given by Newton's formula plus a much smaller "fifth force" that seems to come into play at distances of about 100 to 1,000 meters.

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Hu Ning derived an equation according to general relativity, with the help of Hu's equation and Binet's formula, in reference [8] we derived the following improved Newton's formula of universal gravitation