Answer:
The transmitted intensity through all polarizers is 
Explanation:
According to Malu's law the intensity of a polarized light having an initial intensity
is mathematically represented as

Now considering the polarizer(The polarizing disk) the equation above becomes

Where n is the number of polarizers
Substituting
for the initial intensity 3 for the n and 20° for the angle of rotation


Answer:
Please refer to the figure.
Explanation:
The crucial point here is to calculate the enclosed current. If the current I is flowing through the whole cross-sectional area of the wire, the current density is

The current density is constant for different parts of the wire. This idea is similar to that of the density of a glass of water is equal to the density of a whole bucket of water.
So,

This enclosed current is now to be used in Ampere’s Law.

Here,
represents the circular path of radius r. So we can replace the integral with the circumference of the path,
.
As a result, the magnetic field is

Even population distribution refers to a type of population distribution in which the arrangement is done in such a way that the distance between neighboring individual is maximized and uniform. This type of population distribution is usually found on the farm land, where the space in which the crops are planted have been carefully measured out. Thus an example of even population distribution is corn planted in a field.
It weakened the gravitational force between the oblects.
Now the vertical velocity of the ball thrown at an angle 10° is given as
Voy(initial vertical velocity)= 30m/s x sin 10
Voy(initial vertical velocity)= 5.2m/s
Now the ball is decelerating with an acceleration due to gravity equivalent to 9.8m/s^2.
Let Vy be the final velocity and that is equal to zero in this case.
Now
Vy= Voy- tx9.8
Where t is the time at which the vertical velocity becomes 0.
Substituting the values we get
0= 5.2-tx9.8
9.8t=5.2
t=0.53 secs