   A heavier plane has more momentum (when thrown at the same speed),  but it's also got more downward force acting on it. If it has the  same wing area, though, it has the same lift, so it drops more  quickly than a light plane (objects fall at the same speed only in  the absence of air resistance).
By 2 months, baby's bedtime should be between 6:00-8:00pm and should occur about 1 hour after the last nap ends. 3 months: babies this age should be on a solid 4 nap schedule with the last nap of the day ending by 5:00pm.
Have a regular and quiet bedtime routine. Around 12 weeks, babies can begin to develop a regular circadian rhythm thatâs dictated by the cycle of night and day. This means early on in life, your baby can start getting used to a bedtime routine that will signal sleep is coming soon.