I think it's C, longer wave length.
Answer:
Color, Streak, luster, cleavage and fracture, hardness, crystal shape, and density.
Explanation:
Given parameters:
Displacement = 8km
Velocity = 3.8km/h
Unknown:
time = ?
Solution:
Velocity is displacement divided by time.
Velocity =
Displacement = velocity x time
Input the parameters:
8 = 3.8 x time
Time =
= 2.1s
The time taken is 2.1s
Answer:
(a) 
(b) 
(c)
(d)
Solution:
As per the question:
Refractive index of medium 1, 
Angle of refraction for medium 1, 
Angle of refraction for medium 2, 
Now,
(a) The expression for the refractive index of medium 2 is given by using Snell's law:

where
= Refractive Index of medium 2
Now,

(b) The refractive index of medium 2 can be calculated by using the expression in part (a) as:


(c) To calculate the velocity of light in medium 1:
We know that:
Thus for medium 1
(d) To calculate the velocity of light in medium 2:
For medium 2:
Answer:
Book. Bottle. table are some examples of objects in equilibrium found in classroom