President Ke Car Pr Number Plate Kyu Nhi? #shorts #youtubeshorts

In a town, the car plate numbers contain only three or four digits, not containing the dit 0. What is the maximum numbers of cars that can be numbered?

Dekhte he pta karein ki number 3 se divide hoga ke nhi

Dekhte he pta karein ki number 4 se divide hoga ke nhi

When the intensity of radiation incident on photographic plate is increased keeping frequency constant, thenthe number and K.E. of photoelectrons emitted?

How many differennt car licence plates can be constructed, if the licences containn three letters of the english alphabet followed by a three digit number, (i) if repetition are allowed? (ii) If repetitionn are not allowed?

In the photoelectric effect the eletrons are emiited intantaneously from a given matal plate when it is irradiated with radiation of frequency equal to or greater then some minimum ferquency, is called the threshold frequency.According to Planck's idea, light may be considered to be made up discrete particles called photons.Each photon carries energy equal ti hv.When this photon cllides with the electron of the metal, the electron acquires energy of the emitted electron is given by : hv=K.E_("maximum")+PE=(1)/(2)m u^(2)+PE If the incident rediation is of threshold frequency the electron will be emitted without any kinetic energy i.e hv_(0) :.(1)/(2)m u^(2)=hv-hv_(0) A plot of kinetic energy of the emitted electron versus frequency of the incident radiation yields a straight line given as : The number of photoelectrons emitted depends upon :