A trolley is moving horizontally with a velocity vm/s wrt to earth . a man starts running on the trolley with a velocity 1.5v m/s wrt to the trolley . After reaching the opposite end the man turns back and continues running with a velocity of 1.5v m/s wrt trolley in the backward direction if the length of the trolley is l then the displacement of the man wrt earth measured as the function of time will attain its max value of
