Quantum

Question 1

What is the photoelectric effect?

Answer 1

When electrons are released from the surface of a metal plate when a high enough frequency is shined onto the plate.

This frequency usually falls in the ultra violate range.

Question 2

How does the photoeletric effect work?

Answer 2

The electrons absorbe energy from the radiation making them vibrate. More energy breaks the bonds holding the electron to the metal, The electron is released.

Question 3

What can increase the maximum kinetic energy?

Answer 3

The frequency of the radiation

Question 4

Describe an electroscope

Answer 4

• Zinc plate negatively charges- metal in box also
  gold rises up cause negative charge repels the gold.
• when uv shone ellectrons emmintted, photoeletric effect, zinc plate losses its negative charge.
• gold leaf nolonger, reppeled falls back down

Question 5

When do electrons move down energy levels?

Answer 5

When they emmit a photon

Question 6

How do fluorescent tubes work?

Answer 6

• contain Mucury vapor across a high voltage.
• Voltage accelerates fast-moving free electrons that ionise some mucury atoms, makes free moving electrons
• flow of free electrons collides with electrons in the mercury atoms, atomic mucury electrons become excited.
• When the de excite they emmit high energy photos is the uv range (range of energies and wavelenghths)
  -Phosphor coating on tube absorbes photons, exciting its electrons to higher energy level, loeses energy by emmiting lower energy photons of visible light.
  Murcury Voltage Accelerates Elelctrons Ionises Collide Excited Uv Phosphor exciting MVAEICEUPE