Answer: The light bends because light travels fast but it slows down in a denser medium. For example light refracts in water or it bends after passing through air. When light passes through air ( a less dense medium ) then through water ( a more dense medium ) the beam of light bends because light travels more slowly in a denser medium then it picks up its pace again once it passes. The density of the substance determines how much the light is refracted. I hope this makes sense and I hope this answered your question!! :)
Answer:
a) 17 km
b) 9 km
Explanation:
The distance is the length of the path.
A to C: 5 km
B to C: 4 km
C to B: 4 km
B to C: 4 km
Total distance = 5 km + 4 km + 4 km + 4 km = 17 km
Displacement is the difference between the starting point and ending point.
Displacement = 9 km − 0 km = 9 km
Explanation:
Given that,
Diameter = 10 cm
Distance = 2 m
Speed 
Speed 
Pressure in main pipe 
(I). We need to calculate the diameter
Using equation of continuity
(II). We need to calculate the pressure the gauge pressure
Using Bernoulli equation
(III). If it is possible to carry water to a faucet 17 m above ground,
Using Bernoulli equation
Here, 
Put the value in the equation
Hence, This is required solution.
