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Derive the formula for the maximum kinetic energy of an electron emitted from a metal with work function energy p , that is illuminated by light of frequency f.

The phenomenon this question relates to is the photoelectric effect, and it can only be explained using Einstein’s photon model of light. Electromagnetic waves are emitted in discrete lumps of energy, called...
GR
Answered by George R. • Physics tutor
23347 Views

A note was played on a a keyboard. The frequency of the note was 440 Hz. (a) What does a frequency of 440 Hz mean? (b) The sound waves produced by the keyboard travel at a speed of 340 m/s. Calculate the wavelength of the note.

(a) A frequency of 440 Hz means that a single trough and peak of the sound wave oscillates 440 times per second or equally that 440 sound waves are produced by the keyboard per second (This is because the SI...
IW
Answered by Ifan W. • Physics tutor
40984 Views

A bullet is fired horizontally from a rifle 1.5m from the ground at 430m/s. How far does it travel and for how long does it travel before it hits the ground?

A bullet is fired horizontally from a rifle 1.5m from the ground at 430m/s. How far does it travel and for how long does it travel before it hits the ground? Assuming that air resistance is negligable What's...
TA
Answered by Tim A. • Physics tutor
104085 Views

How does stimulated emission work?

Stimulated emission occurs under the specific circumstances of a population inversion, that is, when there are more electrons in a higher energy level than one below it. There will be a certain energy differ...
KE
Answered by Konrad E. • Physics tutor
6411 Views

How does electromagnetic induction produce a current?

When a wire moves through a magnetic field the wire cuts through the magnetic field lines. This cutting through gives a force on the electrons in the wire, pushing them along, and these moving electrons are ...
KE
Answered by Konrad E. • Physics tutor
4653 Views