Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Nitin meel
In laplacian operater the function is producted(multiplied) two times by the del operator and in divergence it is only once. Generally spherical coordinate system is used to find the location of body/particle on a spherical surface.for example for finding location on earth this system is used.