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)
Paltu Sen
To solve the problems of Doppler effect of sound remember the single formula. when observer approaches source use + sign of Vo and when recedes use ' - 'sign. when source approaches observer use minus sign of Vs and + if recedes. simply you need to increase frequency when source and observer come close together and decrease if when they go away from each other