A glass lens, nglass=1.52, has a 127 nm thick antireflective film coating one side, nfilm=1.39. White light, moving through the air, is perpendicularly incident on the coated side of the lens. What is the largest wavelength of the reflected light that is totally removed by the coating? Assume that nair=1.00.

Explanation:

The optical path length for the reflection of light =

For destructive interference,  

The thickness of the anti-reflective film = 127 nm

The largest wavelength of the reflected light,

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.

im guessing the west of station b