154. Simultaneously, a sma1l part of the galna ray energy i.s converted toel-ectromaE$etic energy through interaction with the surrounding air. A strangelectromagnetic fier-d develops around the explosion and disapplars agai.n in ressthan a millisecond. During its brief existence this riela riaiates Jlectronagneticrraves in approximately the same manner as a radio transmitter aerial, and anykind of electrical cond.uctor rnay act as an antenna and pick up some of theefectromagnetic energ:y. rn this rtranner culrents nay be induced rrhich can d8raAernany types of electrl'.c and - in pa"ticular _ electronic equipment. 155' sone of the neutrons emitted from the explosion vi11 give rise to nuclearreactions by uhich radioactive atoms are created in the ffeapon residues and theair but arso in the soil around ground-zero and in some other materie.ls that ,oaybe hit by the radiation. This induced. radioactivity is in general negligiblecompared to falJ-out activity. 156. when the fireball rises" it cools off and is gradually transforned into ahuge cloud' A column of dust and smoke sucked up from the ground forms the stemof the "mushroomrr. After sorae r-o minutes when the eloud is fu1Iy developed, itvi11 have a dianeter of L-5 kn., while the base is perhaps 6,rra tl. top 10 km.above the ground " 15?. The firebau' and later the c1oud, contains most of the radioactive aroms,rnostl-y fission products, that were formed in the exlglosion. I\rhi 1e the totalweight of these fragments is sma11, about 1kg., their conbined radioactivityone hou-r after the explosion equals that of several thousand tons of radtum
**Analysis**
The text appears to be discussing the immediate effects of a nuclear explosion, specifically the release of radiation and the formation of a fireball and cloud. The language used is technical and scientific, indicating that the text is focused on the physics and chemistry of the explosion rather than any human-related aspects. The text does not mention economic, social, or cultural impacts, and does not provide information on any specific industry, transportation, or communication systems.

**Category**
Science and technology, Health