There are 13 stations on a certain railway line.How many kinds of different single third class tickets have to be printed in order that it may be possible to travel from any station to any other?

There are 17 stations from Howrah to Bandel on the railway line . How many kinds of different single third class tickets must be printed so as to enable a passenger to travel from one station to another?

There are 12 stations on a certain railway line . How many different kinds of tickets of class II must be printed in order that a passenger may go from any one station to any other ?

In a network of railways, a small island has 15 stations. Find the number of different types of tickets to be printed for each class, if every stations must have tickets for other stations.

Out of 8 given points, 3 are collinear. How many different straight lines can be drawn by joining any two points from those 8 points?

Rajdhani Express going from Bombay to Delhi stops at five intermediate stations, 10 passengers enter the train during the journey with 10 different ticket of two class. The number of different sets of tickets they may have is a. ""^15 C_(10) b. ""^20 C_(10) c. ""^30 C_(10) d. none of these

Einstein established the idea of photons on the basis of Planck's quantum theory. According to his idea, the light of frequency f or wavelength lamda is infact a stream of photons. The rest mass of each photon is zero and velocity is equal to the velocity of light (c) = 3 xx 10^(8) m.s^(-1) . Energy, E = hf, where h = Planck's constant = 6.625 xx 10^(-34)J.s . Each photon has a momentum p = (hf)/(c) , although its rest mass is zero. The number of photons increase when the intensity of incident light increases and vice-versa. On the other hand, according to de Broglie any stream of moving particles may be represented by progressive waves. The wavelength of the wave (de Broglie wavelength) is lamda = (h)/(p) , where p is the momentum of the particle. When a particle having charge e is accelerated with a potential difference of V, the kinetic energy gained by the particle is K= eV. Thus as the applied potential difference is increased, the kinetic energy of the particle and hence the momentum increase resulting in a decrease in the de Broglie wavelength. Given, charge of electron, e = 1.6 xx 10^(-19)C and mass = 9.1 xx 10^(-31) kg . The number of photons emitted per second from a light source of power 40 W and wavelength 5893 Å

A train is going from kolkata to Delhi stops at nine intermediate stations. Six persons enter the train during the journey with six different tickets. How many different sets of tickets they have had ?