Bài giảng ĐỀ HAY ĐH 2011 LÝ SỐ 7

http://ductam_tp.violet.vn/ 2011 Môn Thi: VẬT LÝ – Khối A Thời gian: 90 phút, không kể thời gian giao đề  !"#$%$&'"("#()*+*,&'"("#()*"-!+*./ 0(12+3"#4-$(125*!&6"#$("#$7*$%$8(9":;<=:$(>:$3+3"#: ?@"A*<-BC"#$(125*!&6"#$7* "#D"+3"#0 0EF$+3"#4-AG"#&EH"#+3"#4*": ?@": !"#I6:$(120 0.J"&6+3"#:K.I6:&.LI4-B.J"&6$("#$7*$%$8(9":;<=:$(>:$3+3"#: ?@"A*<-BC"#B.J"&6$("# $7*"#D"+3"#0 03"#1M:(N84-+3"#:K! *BO.$%$"#D"1M:(N80#D"1M:(N84-$%$"#D"$3$P"#:9"+Q,$P"#8(*(!R$$3 &64S$(8(*1(T"#&U.0 V !"#:(W"#(.SIX"#,%"(+%"#&EN$5P"#4-%"(+%"#&Y"+Z$$3λ[\,]VµI0(.:(*?%"(+%"#: J"BC"# %"(+%"#&Y"+Z$$3BEF$+3"#λ^:(21(!_"#<":`"#:(JI,V49"0EF$+3"#λ^BC"# 0\,aVbµI0 0bµI0 0a,VµI0 0\,bµI0 c 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Mét ®iĨm M trong vïng giao thoa cã hiƯu ®ưêng ®i lµ 15 cm. Th× biªn ®é dao ®éng lµ cđa M lµ: A. 5cm B. 0 cm C. 20 cm D. 10 cm a3B*A_$9"(r&D"#$(>:1(Q.4EN"#I  ,I V <-I c &EN$#Z":(i!:(l:p:K.$%$&.LI,<-: J"I6: :(*"((2"(: qI_"(,$l"#,$31(Q.4EN"#1(T"#&%"#1L,+*!$(!:(*"(t?J"A*:I$7*$%$A_$90.M:I  [ VI V [V<-[0L1(Q.:I$7*(S"CI:K.: "#&.LI$7*:(21(Q.4EN"#I c BC"# 0Vhc 0hc 0 0V s(.I6:<=: Z"A*?&@A*"(I6:: q$$Q&'"(&.A*<=::(2I6:&.LIt%$&'"(: J"<=:O $%$(: q$A*?1(!_"# ‘\$3 0<i$:Y<=":Q$5-.B.M"&U.0 0&64F"<=":Q$5-.B.M"&U.0 0<i$:Y<=":Q$5-.1(T"#&U.0 0&64F"<=":Q$ #3$B.M" &U.0 j(! đoạn mạch xoay chiều AB như hình vẽ: Để u AM có pha vuông góc u MB thì hệ thức liên hệ giữa R, R 0 , L và C là: A. L = CRR 0 . B. C/L =RR 0 C. L/C = R 0 /R D. 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