Name: 您需要了解的唯一輻射組織、部門 (The Only Radiation Units You Need to Know)
Uploaded: 2021-01-14T10:47:18.000Z
Duration: 6 min 6 s
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基礎被動語態

The term “radiation” is thrown around a lot.

Like, you might have heard that your cell phone

Or maybe you just want to understand whether

those x-rays your doc ordered are dangerous.

conversation about the relative dangers of

radiation exposure without being clear about

And unfortunately, thanks to some accidents

of history, the units we use to measure radiation

and radiation exposure are… kind of a mess.

But there's only two you really need to understand:

In physics, it refers to the energy carried

And to get this one out of the way real quick:

ionizing radiation—they use radio waves,

which don't have enough energy to damage cells.

into smaller chunks, releasing other particles

And how easily these particles can ionize is,

Particle energy is usually given in units

and a typical radioactive particle may have

an energy of about one megaelectronvolt, or MeV.

standard unit of energy – the joule —

by one meter — which has 6 trillion MeVs in it.

generally give off one particle at a time.

per second—basically, a tiny amount of activity.

several thousand becquerels all the time.

but it's now defined as 37 billion becquerels.

Essentially, it quantifies how many electrons

are being knocked off per cubic centimeter of air.

emitting one curie of radiation or in a room

it's not enough to know how many particles

A dose of one gray means that one kilogram

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