At a beach the light is generallypartially polarized owing to reflections off sand and water. At a particular beach on a particular day near sundown, the horizontalcomponent of the electric field vector is 2.3 times the vertical component. A standingsunbather puts on polarizing sunglasses; the glasses eliminate the horizontal field component.(a) What fraction of the light intensity received before the glasses were put on now reaches the sunbather’s eyes? (b) The sunbather, still wearing the glasses, lies on his side. Whatfraction of the light intensity receivedbefore the glasses were put on now reaches his eyes?

a) 0.159

b) 0.84

Explanation:

The Horizontal component is 2.3 times the vertical component

Let the horizontal electric field component =

Let the vertical electric field component =

The formula for light intensity is given by:

..............................(1)

is the resolution of the vertical and horizontal components,

..................(2)

Light intensity before the glasses were put on:

.............................(3)

Put equation (2) into equation (3)

.............................(4)

After the glasses were put on the horizontal component vanishes, i.e.

...................................(5)

Divide equation (5) by equation (4)

...............................(6)

But ......................(7)

Insert equation (7) into (6)

b) When the sunbather lies on his side, the vertical component vanishes, i.e

you cant move and you feel like someones pushing you down onto your bed it can feel like you want to get up but you just can't it can be extremely scary

a solenoid is created by wrapping a l = 90 m long wire around a hollow tube of diameter d = 4.5 cm.   the wire diameter is d = 0.9 mm.   the solenoid wire is then connected to a power supply so that a current of i = 9 a flows through the wire.

randomized variablesl = 90 m

d = 4.5 cm

d = 0.9 mm

i = 9 a                                          

write an expression for the number of turns, n, in the solenoid. you do not need to take into account the diameter of the wire in this calculation.

calculate the number of turns, n, in the solenoid.

write an expression for the length of the solenoid (l2) in terms of the diameter of the hollow tube d.

calculate the length of the solenoid (l2)   in meters.

calculate the magnitude of the magnetic field at the center of the solenoid in teslas.

explanation: