1. April 25 AP Physics

2. In:
A wire loop of radius 0.50 m lies so that an external magnetic field of magnitude 0.20 T is perpendicular to the loop. The field reverses its direction, and its magnitude changes to 0.30 T in 1.5 s. Find the magnitude of the average induced emf in the loop during this time.

3. Objective: To comprehend:
Quantum physics
Photons, the photoelectric effect, Compton scattering
Atomic physics
Atomic energy levels
Wave-particle duality

4. Atomic and Nuclear physics
Quantum physics
Photons, the photoelectric effect, Compton scattering
Atomic physics
Atomic energy levels
Wave-particle duality
Nuclear physics:
Nuclear reactions (including conservation of mass number and charge)
Mass-energy equivalence

5. Attributed to William Thomson, 1st Baron Kelvin 1900
"There is nothing new to be discovered in physics now. All that remains is more and more precise measurement"
Attributed to William Thomson, 1st Baron Kelvin 1900

6. Black body radiation and Max Planck’s quantum theory
German physicist
Founder of quantum theory
Nobel prize 1918

7. Photoelectric effect:

8. Einstein and the photoelectric effect
German born physicist
1905 “Miraculous Year”
Special theory of relativity
Mass/energy equivalency
Photoelectric effect
Brownian motion
Nobel prize 1921

11. Graph for different metals

12. E = hf = pc Kmax = hf - Φ E = energy f = frequency K = kinetic energy
h= Planck’s constant
6.626 x j.s

13. Lithium has a work function of 2. 30 eV
Lithium has a work function of 2.30 eV. If 400-nm light is incident what is the maximum kinetic energy of the photoelectrons.

14. Arthur H. Compton American physicist
Discovered the phenomena called Compton scattering.
Nobel prize 1927

15. Neils Bohr Danish Physicist
Explained atomic spectra with his model of the atom
Nobel prize 1922

22. A stellar spectrum shows three absorption lines of hydrogen produced as electrons move from the n=2 state to higher energy levels (n=3, n=4, n=5) what are the wavelengths and colors of the three lines missing from the continuous spectrum?

23. Louis de Broglie French Physicist
Postulated that matter can behave as a waves
Nobel prize 1929

24. If a wave can be a particle, can a particle be a wave?
λ=h p

26. If the wavelength of an electron is 5
If the wavelength of an electron is 5.00 × 10−7 m, how fast is it moving? (b) If the electron has a speed of 1.00 × 107 m/s, what is its wavelength?

27. Out:
Why do you think that physicists in 1900 thought they had discovered everything?