How do you find the work function for photoelectric effect?
The photoelectric equation involves;
- h = the Plank constant 6.63 x 10-34 J s.
- f = the frequency of the incident light in hertz (Hz)
- φ = the work function in joules (J)
- Ek = the maximum kinetic energy of the emitted electrons in joules (J)
What is stopping potential in photoelectric field?
The negative potential of the collector plate at which the photoelectric current becomes zero is called stopping potential or cut-off potential. Stopping potential is that value of retarding potential difference between two plates which is just sufficient to halt the most energetic photoelectrons emitted.
What is photoelectric effect define stopping potential and photoelectric work function?
(i) Stopping -potential : The minimum negative potential given to the plate for which photo electric current stop or become zero. (ii) Photo electric work function : The minimum energy required to remove electron from a given surface is called photo electric work function.
How do you calculate stopping potential?
To Find: Stopping potential = Vs =? Given: Initial frequency = ν1 = 2.2 x 1015 Hz, initial stopping potential = Vs1 =6.6 V, Final frequency = ν2 = 4.6 x 1015 Hz, Final stopping potential = Vs2 = 16.5 V, Charge on electron = e = 1.6 x 10-19 C.
How do you find the stopping voltage in photoelectric effect?
When the voltage equals the stopping potential, we know that the KE fo the ejected electrons just equals the potential energy at the collector or… KE = PE hf – φ = qV. This equation is very useful. For light shining on the metal, there is a minimum “cutoff” frequency before the ejected electrons have any KE.
What is stopping potential and work function?
The stopping voltage (or stopping potential) refers to the voltage difference required to stop electrons from moving between plates and creating a current in the photoelectric experiment. The minimum amount of energy that is required to eject an electron from the metal surface is known as the work function.
What are stopping potential and work function?
What is stopping potential formula?
Given: Stopping potential = Vs = 2 V, wavelength of incident light = λ = 2000 Å = 2000 x 10-10 m, speed of light = c = 3 x 108 m/s, Planck’s constant = h = 6.63 x 10-34 Js, Charge on electron = e = 1.6 x 10-19 C.
What is work function formula?
In equation form, this is given by KEe = hf − BE, where KEe is the maximum kinetic energy of the ejected electron, hf is the photon’s energy, and BE is the binding energy of the electron to the particular material. (BE is sometimes called the work function of the material.)
What is the stopping potential in photoelectric effect?
The stopping potential is defined as the potential necessary to stop any electron (or, in other words, to stop even the electron with the most kinetic energy) from reaching the other side. What happens in photoelectric effect is that, an incident radiation strikes the surface of the metal.
What is the reverse potential of 1015 Hz light?
For light of frequency 1015 Hz the reverse potential is 2 V. Find Planck’s constant, work function and threshold frequency.
How do you calculate the kinetic energy of ejected electrons?
When the voltage equals the stopping potential, we know that the KE fo the ejected electrons just equals the potential energy at the collector or… KE = PE hf – = qV. This equation is very useful. You can find the stopping potential with V = (hf – ) / q r Frequency and Kinetic Energy
What is the work function of a 10 point photoelectric surface?
(10 points) A sodium photoelectric surface with work function 2.3eV is illuminated and emits electrons. The electrons travel toward a negatively charged cathode and complete a circuit. The potential difference supplied by the power supply is increased, and when it reaches 4.5V, no electrons reach the cathode.