please check these for me:
If atmospheric refraction did not occur, how would the apparent time of sunrise and sunset be changed?
a. both would be later
b. both would be earlier
c. sunrise would be later, and sunset would be earlier
d. sunrise would be earlier, and sunset would be later
C
Interference effects observed in the early 19th century were instrumental in supporting a concept of the existence of which property of light?
a. polarization
b. particle nature
c. wave nature
d. electromagnetic character
C
The acronym laser stands for light amplification by ___ emission of radiation.
a. similar
b. simultaneous
c. spontaneous
d. stimulated
D
Both insulators and conductors can be charged by
a. grounding
b. induction
c. polarization
d. contact
D
Two point charges, initially 1 cm apart, are moved to a distance of 3 cm apart. By what factor do the resulting electric and gravitational forces between them change?
a. 9
b. 3
c. 1/3
d. 1/9
D
Electric field strength depends on
a. charge and distance
b. charge and mass
c. Coulomb constant and mass
d. elementary charge and radius
D
1 answer
#2. correct
#3. correct
#4. correct
#5. correct
#6. wrong. The elementary charge of an electron has nothing to do with it