The number of particles is given by n=−Dn2−n1x2−x1 crossing a unit area perpendicular to X-axis in unit time, where n1 and n2 are the number of particles per unit volume for the value of x meant to x2 and x1. Find the dimensions of D called diffusion constant.
N= no. of particle per unit area per unit time
n1 & n2 = no. of particle per unit volume
x1 & x2 are distance from some reference point.
Dimension of ′N′=[L−2T−1]
Dimensional formula of n1 & n2 =[L−3]
Dimensional formula of x1 & x2 = [L]
N=−Dn2−n1x2−x1
D=−N[x2−x1n2−n1]
=[L−2T−1][L][L−3]
D=[M0L2T−1]