首页
登录
职称英语
Tornadoes, whirlwinds, and watersprouts are rotating funnel cloud air masses
Tornadoes, whirlwinds, and watersprouts are rotating funnel cloud air masses
游客
2024-06-11
30
管理
问题
Tornadoes, whirlwinds, and watersprouts are rotating funnel cloud air masses of small diameter. They are differentiated by the intensity of their rotation and by the surfaces that they traverse. Though tornadoes and whirlwinds both travel over land masses, whirlwinds are atmospheric systems smaller than tornadoes. Watersprouts are tornadoes that form or pass over a water surface. A tornado is a powerful vortex or "twister" whose rotational speeds are estimated to be near 300 miles per hour. The first visible indication of tornado development is usually a funnel cloud. As this funnel dips earthward, it becomes darker because of the debris that is forced into its intensifying vortex. Some tornadoes give no visible warning Until their destruction strikes the unsuspecting victim. Tornadoes often occur in groups, and several twisters sometimes descend from the same cloud base. The forward speed of a tornado is normally 30 to 40 miles per hour. In the short time that it takes to pass, a tornado can cause fantastic destruction. There have been cases reported in which blades of straw were embeded in fence posts. [br] Why do tornadoes appear to be dark?
选项
A、They occur only at night.
B、They are funnel-shaped.
C、They pick up debris from the ground.
D、They are water-laden.
答案
C
解析
这道题的解题关键就是文中"As this funnel dips earthward,it becomes darker because of the debris that is forced into its intensifying votex.”
转载请注明原文地址:https://www.tihaiku.com/zcyy/3629938.html
相关试题推荐
Tornadoes,whirlwinds,andwatersproutsarerotatingfunnelcloudairmasses
Tornadoes,whirlwinds,andwatersproutsarerotatingfunnelcloudairmasses
Tornadoes,whirlwinds,andwatersproutsarerotatingfunnelcloudairmasses
Tornadoes,whirlwinds,andwatersproutsarerotatingfunnelcloudairmasses
Tornadoes,whirlwinds,andwatersproutsarerotatingfunnelcloudairmasses
随机试题
Subwaysareundergroundtrains,whichusuallyoperate24hoursaday.Theya
You_______herthetruth.Itdidn’thelpthesituation.A、needn’ttellB、mustn’tt
钢材在冷拉中先降低,再经时效处理后又基本恢复的性能是( )。A.屈服强度 B
试述血压的测量方法。
A.维生素B B.叶酸 C.维生素C D.维生素B E.铁剂营养性巨幼细
开关柜SF6断路器出现()定性为危急缺陷(A)SF6气体低压力报警(B)SF
《变电运维管理规定第26分册辅助设施运维细则》:每年汛期前对防汛设施、物资进行(
贫血性梗死常发生于A.脾、肾、肠 B.肺、肾、脑 C.肾、心、脾 D.脾、
下列归因因素中,属于内部而稳定因素的是()。 A.能力B.努力C.任务难
立井井筒施工混凝土的分层浇筑厚度一般为( )。A.1.0~1.2m B.0.
最新回复
(
0
)