某乐队举办一场演唱会的收入是7000元，乐队的主唱分得其中的25%，另外5名成员平分余下的

Natural light with intensity I and linear polarized light with intensity 3I both fall on a polarizer, the total transmitted intensity is 2I. What is the angle θ between the axis of polarizer and polarized direction of linear polarized light？ θ = ________°

How is the vitamin content in food determined？

Most labs determine the vitamin content of foods using a combination of two technologies —chromotography, which sorts food molecules based on their molecular weight, and a light emission detector that identifies molecules based on their interaction with light。

To test the vitamin A content in an apple, for example, laboratories first grind the fruit to a pulpy liquid and drop a small sample through a device known as a vertical chromotography column. As the sample falls through the column, smaller molecules move faster while heavier molecules move more slowly. As each molecule drops from the bottom of the column, a monitor sounds out like the blips on an electrocardiogram that ring out each time the heart beats. All molecules pass through the column at specific speeds— vitamin A typically takes 10 minutes — a characteristic that has been previously determined.

When 10 minutes have elapsed, a machine shoots a beam of light through the bottom end of the column and records the wavelength and intensity of light the molecule reemits. If vitamin A is present, it should have reemitted the light at a characteristic 325-nanometer wavelength. The intensity of the light given off is a measure of how much vitamin A is present. So by comparing the intensity of the light given off in the apple sample to the intensity of a known amount of vitamin A, scientists can calculate the amount present in the sample.

To determine vitamin A content in an apple,_____.

A．it has to be ground first

B．it has-to be weighed first

C．it has to be X-rayed first

D．it has to be first treated in a chemical liquid

Concern was expressed about the greater ________ of work being imposed on teachers.

A weight

B burden

C tension

D intensity

All the raps of light reflected from objects are______.

A．of the same intensity

B．of varying intensity

C．to some degree intense

D．not at all intense

All the rays of light reflected from objects are____.

A．of the same intensity

B．of varying intensity

C．to some degree intense

D．not at all intense

A．resistance

B．compensation point

C．infiltration

D．biogeochemistry

A、Direction

B、Intensity

C、Wavelength

D、All of the above

A、reverse-biased

B、forward-biased

C、zero-biased

D、none of the above

The most general approach to visibility is

dE=-Eb_extdx (2.5)

where E is the light intensity of a collimated beam of light, b_extis the extinction coefficient, which is the sum of the four separate b values for light scattering and absorption by gas molecules and by particles, and x is the distance [28]. If the air mass through which one views a distant object is uniform, so that bext is constant, this may be integrated to

(2.6)

The Koschmeider equation [Eq.(2.4)]is based on the visual range corresponding to E/E₀=0.02 when L_V=Δx.

How do you understand "ignite contagious intensity"？

A．To have an increase in strength

B．To communicate easily

C．To make the company collapse