Titanium metal requires a photon with a minimum energy of 6.94×10−19j to emit electrons. if titanium is irradiated with light of 233 nm, what is the maximum possible kinetic energy of the emitted electrons? what is the maximum number of electrons that can be freed by a burst of light whose total energy is 2.00 μj. what is the maximum number of electrons that can be freed by a a burst of light whose total energy is 2.00 μj.

a)

b)

Explanation:

The photoelectric effect consists of the emission of electrons (electric current) that occurs when light falls on a metal surface under certain conditions.  

If the light is a stream of photons and each of them has energy, this energy is able to pull an electron out of the crystalline lattice of the metal and communicate, in addition, a kinetic energy.  

This is what Einstein proposed:

Light behaves like a stream of particles called photons with an energy  :

(1)  

So, the energy of the incident photon must be equal to the sum of the Work function of the metal and the kinetic energy of the photoelectron:  

(2)  

Where is the minimum amount of energy required to induce the photoemission of electrons from the surface of Titanium metal.

Knowing this, let's begin with the answers:

From (1) we can know the energy of one photon of 233 nm light:

Where:

is the Planck constant  

is the wavelength

is the speed of light

(3)

(4) This is the energy of one 233 nm photon

Substituting (4) in (2):

(5)  

Finding :

(5)  This is the maximum possible kinetic energy of the emitted electrons

Since one photon of 233 nm is able to free at most one electron from the Titanium metal, we can calculate the following relation:

Where is the energy of the burst of light

Hence:

This is the maximum number of electrons that can be freed by the burst of light.

explanation:

earth's surface is mainly heated by the absorption of infrared radiation from the sun.

evaporation occurs because molecules in liquid water are warmed ( usually by the sun) and vibrate quicker, becoming less dense and rise.

condensation occurs because molecules in water vapor are cooled and therefore vibrate more slowly thus becoming more dense and eventually fall to earth.

lines of equal barometric pressure on a weather map are called: isobars : lines of equal temp on a weather map are called: isotherms.​

it is given that trillions of microbes make up to 1% to 3% of the body mass.

let's take average of this percentage: 2%

consider the average mass of the human body as 70 kg.

then, trillions of microbes would have mass  

therefore, 100 trillion micro-organisms would weigh:

this is an approximate value and could change depending on the mass of the human body and percentage of the microbes present in it.

average mass per microorganism =