问题
选择题
若从报纸上选一个英文字母“p”,将其剪下,制成玻片标本,正放在载物台上,则在显微镜下观察到的物像是( )
A.q
B.p
C.b
D.d
答案
显微镜成倒立的像.“倒立”不是相反,是旋转180度后得到的像.即上下相反、左右相反.“p”旋转180度后得到的是“d”,因此视野中看到的物像是“d”.
故选D.
若从报纸上选一个英文字母“p”,将其剪下,制成玻片标本,正放在载物台上,则在显微镜下观察到的物像是( )
A.q
B.p
C.b
D.d
显微镜成倒立的像.“倒立”不是相反,是旋转180度后得到的像.即上下相反、左右相反.“p”旋转180度后得到的是“d”,因此视野中看到的物像是“d”.
故选D.
短文填空 |
American schools begin in September after a long summer holiday. There are two terms in a school year. The first term is from September to J 1 , and the second is from February to June. Most American c 2 begin to go to school when they are five years old. Most students are seventeen or eighteen years old w 3 they finish high school. 1._____ 2._____ 3._____ |