2022英语周报七下44答案

ADE据△dA得,在,相下,与成面比,甲的大甲光的波长长,选项A正确;每种单色光在真空中的传播速率是相同的,都是3.0×10m/s,选项B错误;甲光的波长长,红光的波长比黄光的波长长,选项C错误;根据c=v得,甲光的频率比乙光频率低,则甲光的折射率小,由n=snWm得若两种单色光以相同的入射角进入同种介质,甲光的折射角较大,选项D正确;根据sinC=一得,乙光的临界角较小,两种单色光都从玻璃射入空气,逐渐增大入射角,乙光的折射光线最先消失,选项E正确(2)(1)波源S1的振动先传到P,由波源S1振动方程可知,该波的角频率波速d51P10mt1(1分)根据(1分)入=T(1分)可A=4m,T=0.41分)1)波源S2的振动传到P所用的时间为t2=(1分故质点P在0-0.4s内静止不动,0.4-1.0内仅参与波源S的振动s1=6A1=12cm1.0s~1.5s质点P同时参与两列波的振动,两列波频率相同,发生干涉1分8=|S1p易得分故质点P为振动减弱点其振幅为A,=|A1-A2|=3cms-1.5s质点P的路程为分)2=5.A=15cm(1分)故质点P在t=0至42=1.5内通过的路程为5=s1 s2=27cm(1分)

书面表达One possible versionDear JackI am glad to hear that you will come to our school as an exchange student next year. Since you want toknow about my school, i am writing to introduce some details to you.My school lies in the southeast of our city with convenient transportation, so it will be easy for you to comefrom the airport. The school, where various flowers and fruit trees can be found, provides a pleasantenvironment for students to study in. My school has three grades and almost 1, 000 students altogether andnearly two-thirds of graduates are admitted to key universities every year. Above all, they are friendly andhelpful. Therefore, if you have any difficulty adjusting to your future life, everyone, including me, will give youa handLooking forward to your coming.YoursLi hi

以上就是2022英语周报七下44答案，更多英语周报答案请关注本网站。