2.4 WAVE-PARTICLE DUALITY

Question 1

The photoelectric Effect

Answer 1

is the emmemission of electrons from a metal surface when light is shone onand provides evidences for the particle nature of light

Question 2

To observe photoelectric effect

Answer 2

a zinc plate must be negatively charged and shone with UV

Question 3

WAVE-PARTICLE DUALITY

Answer 3

The idea that light can act both like a wave and like a particle without contradiction (протиріччя)

Question 4

For photoemission to occur

Answer 4

1. the energy of photons must be greater than the work function of the metal
2. the frequency of the photons must be greater than the threshhold frequency

Question 5

The minimum frequency needed to ejects electrons from the surface of the metal is called

Answer 5

threshold frequency fo

Question 6

To increase photoemission

Answer 6

increase the Irradience (brighter source for visible light) which produce more photons each second to eject more electrons each second

Question 7

WORK FUNCTION Eo

Answer 7

the minimum energy required to realeased an electron from a metal surface

Eo=hfo

Question 8

energy of photon is

Answer 8

Ephoton=Ek + hfo

Question 9

Irradiance is

Answer 9

the power per unit area of electromagnetic radiation incident on a surface

I=P/A or I=Nhf where N is a number of photons

Question 10

Photoelectron is

Answer 10

an electrom emitted from the surface of the a material due to a photon incident on the material

Question 11

Photoemission

Answer 11

the emission of the photoelectron from the surface of a material in the photoelectric effect

Question 12

photon is

Answer 12

a particle of light that can also be thought of as a short burst of the wave energy (можна розглядати як короткий спалах хвильової енергії)

Question 13

ELECTROSCOPE

Answer 13

CONSISTS OF A METAL PLATE, METAL ROAD AND GOLD LEAF
the deflection of the gold leaf can be used to investigate the photoelectric effect