When she starts out, he is (40x2.5)= 100 miles ahead of her.
She gains (65-40)= 25 miles on him every hour.
It takes her (100/25)= 4 hours to catch up to him.
Answer:
The correct option is H
Explanation:
From the question we are told that
The index of refraction of coating is
The index of refraction of material is 
Generally the condition for constructive for a thin film interference is mathematically represented
![2 * t = [ m + \frac{1}{2}] \frac{\lambda}{n_1 }](https://tex.z-dn.net/?f=2%20%2A%20%20t%20%20%3D%20%5B%20m%20%20%2B%20%5Cfrac%7B1%7D%7B2%7D%5D%20%5Cfrac%7B%5Clambda%7D%7Bn_1%20%7D)
Here t represents the thickness
For minimum thickness m = 0
So

=> 




//
I'm not really sure but I do know that it's not 0 because the object is still moving, even if it's only moving at 1 m/s.