I can answer the first question: Water rises because of the sun's heat and turns into water vapor. After that, it gathers up and forms a cloud. When the cloud is filled enough with vapor, precipitation occurs.
Answer:
Explanation:
V = 100sin(ωt) + 150cos(ωt)
let x = ωt
V = 100sin(x) + 150cos(x)
a maximum or minimum will occur when the derivative is zero
V' = 100cos(x) - 150sin(x)
0 = 100cos(x) - 150sin(x)
100cos(x) = 150sin(x)
100/150 = sin(x)/cos(x)
0.6667 = tan(x)
x = 0.588 rad
V = 100sin(0.588) + 150cos(0.588)
V = 180.27756
as the maximum will not occur until ωt = 0.588 radians, for a cosine function we subtract that amount as a phase angle φ
V = 180.3 cos(ωt - 0.588)
or as a sine function, the phase angle lags the cosine by a difference of π/2
V = 180.3sin(ωt - (0.588 - π/2)
V = 180.3sin(ωt + 0.983)
Answer:
The intensity of light passing from the third polarizer is 3Io/16.
Explanation:
The law of Malus is given by

Let the incident intensity of light is Io.
The intensity of light passing from the first polarizer is

The intensity of light passing from the second polarizer is

The intensity of light passing from the third polarizer is

Answer:
Speed of the wreck after the collision is 65 km/h
Explanation:
When a car hits truck and sticks together, the collision would be totally inelastic. Since the both the vehicles locked together, they have the same final velocity.
Mass of car 
Mass of truck 
Initial speed of the car 
Initial speed of the truck 
The final velocity of the wreck will be

since final speed are same, 


Due to rotation of Earth on each day, our East & west gets change in every half day, and comes in it's initial state after a day. So, Stars which are in east relative to a stationary object in the Universe, will be in west relative to Earth after some time, and it changes our view of stars
Hope this helps!