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What is the maximum frequency photon of one of the photons produced when a electron and positron annihilate each other?

First we must remember that a positron is the antiparticle of the electron, meaning that they will both have the same amount of rest energy (0.510999 MeV) however since annihilation produces 2 gamma photons ...
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A photon of wavelength 656.3nm is emitted in the Balmer series of a Hydrogen emission lamp. (a). Show that the frequency of the photon is 4.57*10^14 Hz. (b).Use the Planck-Einstein relationship to calculate the energy of the photon.

(a). Firstly, pull out useful information . λ=656.3nm Secondly, identify relevant equation and rearrange to find frequency. λ=c/f => f=c/λ Calculate frequency using the given values (c=3 10^8 m/s), ensuri...
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Answered by Robert M. • Physics tutor
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If a star with a radius of 600000km has a surface temperature of 6000K, calculate its luminosity

Use the formula Luminosity = (Surface temperature)^4 Surface area Stefan's constantCalculate surface area with 4 pi radius^2Area=4.52 10^18therefore luminosity= 4.52 10^18 * (6000)^4 * 5.67 10^-8luminosity =...
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A railway car of mass m1 travelling at a velocity of v1 collides with a second car of mass m2 travelling at v2 and the two join together. What is their final velocity?

Momentum is conserved in any collision, and for a single body is given by p = mv. The momentum before is m1 v1+m2 v2, and the momentum after is (m1 + m2) u where u is the final velocity, so the final velocit...
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Discuss a use and a harmful effect for three parts of the electromagnetic spectrum

Gamma rays can be used to sterilise medical instruments, however, they can cause cancer.Ultraviolet waves can be used for security on bank notes, however, they can cause sunburn and blindness.Microwaves can ...
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Answered by Oliver E. • Physics tutor
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