时间:2019-01-22 作者:英语课 分类:英语时差8,16


英语课

Exploding Trees In a scene from Mary Shelley’s famous novel Frankenstein, one of the characters watches as a lightning bolt strikes a large oak tree. The tree is utterly 1 destroyed in a gigantic explosion. This might be good story-telling, but could such a thing really happen? Let’s find out. Lightning is nothing more than electricity: a LOT of electricity. A single bolt carries a peak current that’s ten thousand times what an average light bulb would use. All this electricity has only one aim: to travel between the clouds and the ground along the easiest possible route. Trees, which stick out of the ground like natural lightning rods, make this route a little bit easier. What happens when lightning strikes a tree depends in part on how long it’s been raining. Water is a much better electrical conductor than wood, and if the tree is thoroughly 2 wet, the bolt will travel along the water that soaks the tree’s bark. This might singe 3 the tree, but it probably won’t kill it, and it certainly won’t make it explode. If the bark is dry however, the next easiest path for the bolt is inside the tree, through the damp, sugary sap. A lightning bolt contains enough energy to bring a ton of water to the boil, so the sap is instantly vaporized. Like a pressure cooker with no safety valve, the tree will indeed explode, just like Mary Shelley reported. What’s more, Mary Shelley’s exploding oak tree is scientifically accurate in another way. Oak trees have particularly rough bark, and it takes rain longer to soak them than smooth-barked trees. This makes oaks especially vulnerable to lightning explosions.



adv.完全地,绝对地
  • Utterly devoted to the people,he gave his life in saving his patients.他忠于人民,把毕生精力用于挽救患者的生命。
  • I was utterly ravished by the way she smiled.她的微笑使我完全陶醉了。
adv.完全地,彻底地,十足地
  • The soil must be thoroughly turned over before planting.一定要先把土地深翻一遍再下种。
  • The soldiers have been thoroughly instructed in the care of their weapons.士兵们都系统地接受过保护武器的训练。
v.(轻微地)烧焦;烫焦;烤焦
  • If the iron is too hot you'll singe that nightdress.如果熨斗过热,你会把睡衣烫焦。
  • It is also important to singe knitted cloth to obtain a smooth surface.对针织物进行烧毛处理以获得光洁的表面也是很重要的。
学英语单词
after leech
AGR fuel element
antiwetting
Anulifera
artmaker
babyproofers
beszel
Bird's formula
Borgosesia
bridge calculating circuit
brighten the chain
Bruecke's reagent
bunder
calamagrostis pseudophragmites koeler
catechizing
Cemaes Bay
chaincessation
choledochus cyst
clamp splice
combined bearing
conversionary
dielectric loss characteristic
dry-sand mould
dynamic data bass parameter
electronic conference system
elliotii
Etla
externally maintained field
extinguishment reserve
extractum liquiritiae
false buckthorn
fidgetiest
foliar application
frozen wall
Fuwa
gelatino-bromide paper
gone green
grapeseed
greased lightnin'
greater-than match
Haribo
heulandites
holocrine secretion
Hospitalet
hull aspirator
incomplete hallucination
indenoindene
keep guard over
lead optimization
luxazone
lyond
Lüllau
machine utilization index
mass spectroscopy
Mcgee graph
meguires
micturition reflex
mulier
multischool
northern holly fern
Obutin
open-ended system
phosphorescence of dyes
phosphoribosylpyrophosphate
photoconductivities
pilot flood
pinselin
pollen plate
Posada de Valdeón
prepared pianos
preproperous
printed-wiring armature
pyranoid
quick balance
rank statistics
reliability design analysis
reopen
report processor
ring-silicate
Ruhmkorff coil
sawnce bell
scarcity of budgetary resources
seepage control installation
shingle bank
sneuel
sprayregen
step printing
straight firing
subsextuple
Swedru
syringocoele
teeth-chatterings
Thamugadi
there-
thermogenic soil
Tupamaro
Twitney Spheres
vicarship
virelai
vitrophyre
white matter (or white nerve substance)
zardaris