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
a smash
anterior radial vein
Aosta,Valle d'
appearance ratio
Australian sword lily
Avia, R.
be limited to
berberis canadenses
bilaminar blastoderm
Bjφrkelangen
bubble axis
bulkhead web
channichthyids
chlorprenaline
cinematising
clamart
Clematis pseudopogonandra
client platform
conditionning
cost per mille
cost-prohibitive
cross intensity function
cystic sinus of sacrococcygeal region
dead-letter office
degrees of frost
Dehydropodophyllotoxine
dextrinised starch
dictionary entry
direct probability
duben
E. I. S.
ectopia of heart
ekblom
electric power substation
extremitas uterina
final polishing pass
fitting locker
forest maturation
formosa aboriginal culture village
fracture of shaft of tibia and fibula
funny
genus Acroclinium
ghosts
Gleditsia formosana
goaneran
grazing preference
I don't mind
idees
inertia frequency
isovaleric acid isobutyl ester
jivadaya
jumblement
lack of supplies
liliopsid genera
magic mountain
maple heights
march to the beat of a different drum
multiplicative array
needle aspiration
neotoxoptera formosana
not amount to much
novatrin
numbering of property
operating lever articulation
pathoadaptation
permanganyl
phants develop in an unhealthy way
photomultiplier effect
pin tuck
polyisobutylenes
posterolateral central arteries
potentiometer with switch
power-ratio method
privalova
pruning machine
psychohistoric
punched card verifier
pupillise
pyromucylchloride
reflex paralyses
snake venom poisoning
socioscientific
sosin block instrument
spermatophylaxes
state prison
steam and water radiator
stromatolith
supersonic bang
suspence
syzygetic pencil
Sūq al Ithnayn
tanjungbalai (tandjungbalai)
tea-cups
Tioglisynth
Tlhakgameng
triply primitive cell
unfair stress
unpunctuate
valamite
varioplex
Walpia
wedge wire cloth