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
absolutely unbiased estimator
Acer pilosum
activation block
adimate
air - cushion vehicle
Al Mu'allaqah
alpha sulphur
American plaice
Asiaphile
awardment
barium trithionate
bark rubber
Bechterew's disease
Beladice
benzyl amygdalate
bigger bang for a buck
bird and beast pattern
bisseuil
black-widow spider
blackout powder
Bowen fluorescence mechanism
buying on
C. A. R.
Celastrus virens
chrom-
convertible security
cooled cell radiometer
croquet-ground
desolates
diaphragm type air spring
dimension lumber
Diovan
directly projective element
dows
ebullating bed
epipremum giganteum schott
free surface
freerode
galvanized layer thickness
gedicks
gogar
Gorda, Punta
grease storage tank
hoatzins
icily
implementation evaluation
jiggling
Juliana, L.
loading variant
lophiostomate
magnetic crystal
marble mosaic
median selector
molecular force field
monovanadium disilicide
morbus coxae
mother bulb
naval hydrodynamics
new species(n. sp.)
non-shrink
organoosmium
osteitis fibrosa osteoplastica
outlined fone
peak drifting effect
Pecém
pelts
phase-amplitude indicator
photo-trichromatic
postmultiplies
pre-Chellean
pseudo-asymmetry
public goods game
pyrgotid
quilting cotton
radulas
rationalized units
right side cerebral rigidity
right-eye image
rock-drills
sacbrood
Sagittaria wuyiensis
samarangs
schistosis
single shaft inertia shaker
skin fragility
solid switch
stereoelectroencephalographic
subnormal subgroup
superconducting bridge
synchronors watt
the wicked one
three-dimensions heat treatment
town planners
tree science
trigly
twelvefoldness
two-leg
under-compansated meter
virtual desktop manager
wallhackers
wild medlar trees
Witzwort