Sunlight passes through a couple of polarizers. if the transmitted brightness is 20% of the sunlight brightness, calculate the angle, rounded to the nearest tens of degrees, between the polarizers. a. 20° b. 30° oc. 40 d. 50° e. 60°

option D= 50°

Explanation:

When sunlight passes through the first polarizer, the intensity reduces to its half

that is .........(1)

let the angle between the polarizers be θ

then we know that the intensity of light after passing through second polarizer is

⇒............(2)    from (1)

also given that ..............(3)

equating 2 and 3 we get

on solving the above equation we get

θ= 50.75°≅50°

hence the angle between polarizers is 50°

option D is correct

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.