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
Abbott's bearing curve
acylglycerophosphoglucose
additive zero one algorithm
alveococcosis
Attawapiskat
balanced voltage
Ballaghaderreen
bannons
Bartle
bastnasites
be on edge
benzimidazoyl
biology of marine mammals
blonde bombshell
bring sb. to heel
bs(british standard)
capacitance sensor
cetology
charadrius mongolus mongolus
chorophobia
concussion of spinal cord
continuing warranty
cost minimization principle
couglin
credit extensions to overseas non-residents
dhobie
digoxin
Downers Grove
earnings per share ratio
electropneumatic signal
Ephebaceae
face-centered cubic lattice
factory overhead applied
freepoint indicator
Hadhramautian
halophyte salt-secretion
herrerae
holocoder
honeyflower
host language interface
Ilex tenuis
inertia constant of a set
intake sluice
intower
jarrat
key material identifier
laminated-fabric plate
lipoprofein
low island
luminous flux (i)
mbuji-mayi
messangier
monetary gain or loss on long-term debt
multicolor holography
mutualism
National Geographic Magazine
navicoes
noresidue at harvest time
Norpac
nucleus originis accessorius (parasympathicus) n. oculomotorii
oleo strut
on vehicle survey
organizing function
Ottenby
paged algorithm
planetocentric
ploughings
porcelain ball for graining machine
posteroventrally
potassium lanthanum nitrate
product types
propeller set
property passing on a death
Qala Shinia Takht
QHD
rate of displacement
reach the standard
relvar
Rh-negative blood
security appliance
self-routing switching
selling price variance
semishrouded impeller
shakeup
shemales
Silba
silent holocaust
spermatists
sphyraena jello
strength data
supraoccipital
surface type starter
Target zones
tarsal cartilages
the rope
torusknot
trochlear fossa
vinbarbital sodium
washery slag
well-brushed
whited out
wound-ups