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
-splain
acid resisting metal
advanced-level
alchemistry
ameritech
anachorite
apotomin
astraspiss
auricular projection
autochart
berardiuss
biological diversity
blue-pus bacillus
bog walk
butterhead lettuce
Byelarus
Cache-Coherent Non-Uniform Memory Access
Carex nervata
civil aeromedical institute
class hyalospongiaes
climatic therapy
coefficient of residual gas
combined cyclone and demister separator
commercial call
cordial reception
cornice vent
COSCO Shanghai
credit support
cyrus iis
deviled ham
driven in pin
encaustically
euripidess
expellent
fabiolas
filament blend yarn
flame descaling
flybelt
fore topsail
gamb,gambe
genus Elettaria
glacial landform
Goll's nucleus
growth poles
guidanuce system inertia
hand brake lever rod
helper application
heptapodies
horripilates
Hydrolagus
Hydroxy-5-methylflavone
Hιnιs
image focus voltage
Ingelow, Jean
kavieng
kick sb in the teeth
krotovina
latherable
leatheriness
liquid self-hardening sand
maximum contents length
mesopause
mixed-gender
mode amplitude
muscle bones
net profit earnings
net refrigerating effect
Northern Dvina River
ordinary differential equation (ode)
Osmedysphoria
parasite elimination history
Pender County
perpendicle
personage
physiologic space
pickfork
propharynx
puccinia kurosawae
radiological accident
rain arc-over test
range algorithm
Regalecidae
rent on real estate
roughened
saddle bow
scientific community
screen write transaction program construction
significant other,
spermio-
spherical divergence
spontaneous potential curve
Syncalathium qinghaiense
take one's point
this year
two-dimensional code
ultegra
unknelled
uphills
Venorrhaphy
very low frequency band radiated field system
welder's gloves
Wormit