   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.
Sleep and Toddlers (1-2 years). Toddlers need about 11-14 hours of sleep in a 24-hour period. When they reach about 18 months of age their naptimes will decrease to once a day lasting about one to three hours.Naps should not occur too close to bedtime as they may delay sleep at night.leep and Newborns (0-3 months). For newborns, sleep during the early months occurs around the clock and the sleep-wake cycle interacts with the need to be fed, changed and nurtured. Newborns sleep a total of 10.5 to 18 hours a day on an irregular schedule with periods of one to three hours spent awake.