更多"Some crystals emit visible light wh"的相关试题:
[单项选择]Some crystals emit visible light when ______ by ionizing particles.
A. burned
B. struck
C. excited
D. inspired
[单项选择]I'd rather you did some housework when you are free, but you ______.
[单项选择]______ had asked him to bring some apples when he came, ______ he forget it at all.
A. Though; but
B. Though; /
C. Till; /
[单项选择]Plants will emit an increased amount of heat when they are ______.
A. sprayed with pesticides
B. facing an infrared scanner
C. in poor physical condition
D. exposed to excessive sun rays
[单项选择]--Must I turn off the light when I leave --No, ______
[单项选择]The new facts throw some light () the matter.
A. at
B. in
C. on
D. of
[单项选择]When summer comes and the light—colored people go to the beaches, ______.
A. all of them will tan darkly
B. few of them will tan darkly
C. many of them will not tan at all
D. some of them will not tan at all
[单项选择]— Must l turn off the light when I leave
— No,______.
[单项选择]Some people prefer to remain anonymous when they call the police to report a crime.
A. undisturbed
B. unnoticed
C. unrecorded
D. unnamed
[单项选择]When light illuminates an object, part of it is absorbed and part reflected, the ________lightness of an object depends on the proportion of light that is reflected.
A. denoted
B. embodied
C. insulated
D. perceived