47. A man is nearsighted and cannot see things clearly beyond 110 cm from his eyes. What is the focal length of the contact lenses that will enable him to see very distant objects clearly?
(A) 50 cm
(B) -50 cm
(C) -110 cm
(D) 110 cm
(E) -30 cm.

答案:登入後查看
統計: A(0), B(0), C(14), D(1), E(1) #3093888

詳解 (共 3 筆)

#7230052
這是一道關於幾何光學中視力矯正(近視)的...
(共 1947 字,隱藏中)
前往觀看
0
0
#6302937
“cannot see clearly ...
(共 167 字,隱藏中)
前往觀看
0
0
#7230172
這是一道關於幾何光學中「視力矯正」的經典...
(共 2336 字,隱藏中)
前往觀看
0
0