首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
考研
Experienced baseball fielders can tell how far a ball is going to travel just by listening to the crack of the bat. If they didn
Experienced baseball fielders can tell how far a ball is going to travel just by listening to the crack of the bat. If they didn
admin
2010-01-13
102
问题
Experienced baseball fielders can tell how far a ball is going to travel just by listening to the crack of the bat. If they didn’t, they wouldn’t stand a chance of catching it, claims a physicist in New York.
"When a baseball is hit straight at an outfielder, he cannot quickly judge the angle of the scent and the distance the ball will travel," says Robert Adair, a physicist at Yale University. If he relied purely upon visual information, the fielder would have to wait for about one-and-a-half seconds before he could tell accurately if the pitcher hit the ball long or short. By this time the ball may have travelled too far for him to reach it in time.
To stand a fighting chance of catching it, according to Adair, fielders must listen to the sound the ball hitting the bat to judge how far it will travel. There is anecdotal evidence to support this, he says. A former centre fielder told Adair: "If I heard a crack I ran out, if I heard a clunk, I ran in."
To test his hypothesis, Adair calculated how quickly a fielder could change direction if he had misjudged whether the ball was going long or short. The difference between the "crack" and "clunk” can he explained by how well the batter has hit the ball, and could mean a difference in running distance of as much as 30 metres, he told delegates at a meeting of the Acoustical Society of America in Chicago last week.
Scientists already knew that to hit a ball long the batter must strike it somewhere near the vibrational node of the bat, known as the sweet spot. Balls hit on the sweet spot generate fewer energy-sapping vibrations in the bat, allowing greater energy transfer to the ball. Conversely, mishit balls make the bat vibrate strongly and so do not travel as far.
Adair is quick to point out that this only applies to wooden bats, which are used in major league baseball. Aluminum bats, on the other hand, tend to produce a fairly uniform "ping” sound regardless of where you hit them.
Which of the following statements best summarizes the main idea of this passage?
选项
A、Hitting the ball to produce different sounds is not an easy matter.
B、The sound of the bat may give fielders more chances to catch the ball.
C、Aluminum bats are inferior to the wooden ones.
D、The study of Robert Adair shocks the Acoustical Society of America.
答案
B
解析
主旨大意题。本文主要讲的是防守队员如何根据球击在木质球棒上的声音来判断球的飞行距离。
转载请注明原文地址:https://kaotiyun.com/show/Zjmi777K
0
在职申硕(同等学力)英语
相关试题推荐
女性,55岁,肥胖。半年前无明显诱因以双膝关节间歇性疼痛,以右侧为重,劳累时加重,休息后缓解,自觉关节活动不灵活,可伴粗糙摩擦声。查体:膝关节肿胀,股四头肌轻度萎缩,关节间隙有压痛,关节活动时有摩擦感。辅助检查:X线示膝关节边缘有骨质增生,关节间隙正常,软
Visualimpairment(视觉障碍)carrieswithitareducedorrestrictedabilitytotravelthroughone’sphysicalandsocialenvironmentu
Desperatelyshortoflivingspaceanddangerouslypronetoflooding,theNetherlandsplanstostartbuildinghomes,businessesa
The______choiceforaconsumer,therefore,isthechoiceamongtheavailableonesthatwillenablehimorhertomaximizeutil
Thereis(fewevidence)thatchildren(inlanguageclassrooms)learnforeignlanguages(anybetter)thanadultsinsimilar(clas
WhatdoTimeWarnerandMatsushitahaveincommon?Whichofthefollowingistrueofthemedia?
Experiencedbaseballfielderscantellhowfaraballisgoingtotraveljustbylisteningtothecrackofthebat.Iftheydidn
JudgmentwassuspendedtillthefollowingMondaybecauseofthelackofevidence.
A:Sorry,teacher.Iforgettobringmyhomework.B:______
Everyyeartelevisionstationsreceivehundredsofcomplaintsabouttheloudnessofadvertisements.However,federalrulesforbi
随机试题
A.阴凉、通风处B.密闭、阴凉处C.阴凉、干燥处D.通风、干燥处E.密封、凉暗处含糖分及黏液质较多的饮片,如肉苁蓉、熟地黄、天冬等,应贮于
某市律师协会与法院签订协议,选派10名实习律师到法院从事审判辅助工作6个月,法院为他们分别指定一名资深法官担任导师。对此,下列哪一说法是正确的?(2017年卷一7题)
下述中哪一条符合汽车库安全疏散的要求?
下列有关分析程序的说法中,错误的是()。
控制图是一种()。
()是我国首个被联合国教科文组织人和生物圈保护区、世界地质公园、世界遗产三大保护制度共同录入的“三冠王”名录遗产地。
把立方体的8个角削掉就能得到一个边长固定,只包括正方形与正三角形两种面的古罗马骰子,把三角面涂红色,正方形面涂黄色,红、黄两种油漆的用量比为:
民歌按照题材来分,包括劳动工作的号子,谈情说爱的情歌,流传于各族儿童中的歌谣,饮酒作乐的时曲,纪念亲人故友的挽歌,劳动休闲时吟唱的小调,还有民间经常唱的山歌等等。山歌
Whomdidthemanandthewomantalkabout?
Tomhasgrownupand______(强烈反对被当成小孩子).
最新回复
(
0
)