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A neutron has a charge of zero coulombs and a mass of 1.67 times 10 to the negative 27th kilograms.
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What is the charge-to-mass ratio of a neutron?
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Given the charge and mass of some object, in this case a neutron, its charge-to-mass ratio is simply its charge divided by its mass.
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In symbols, weβd write the charge-to-mass ratio as capital π divided by π, where capital π is the charge and π is the mass.
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The units of this quantity are whatever units we use for charge divided by whatever units we use for mass.
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For this particular question, the calculation is quite easy because the neutron has a charge of zero and a mass that is not zero.
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Therefore, when we divide charge by mass, we have zero divided by a number that isnβt zero, the result of which is just zero.
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Carrying over the units, this gives us a charge-to-mass ratio of zero coulombs per kilogram.
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A charge-to-mass ratio with a numerical value of zero is characteristic of all neutral particles with nonzero mass, like the neutron.
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Particles like the photon that are neutral but also have zero mass do not have a well-defined charge-to-mass ratio.