In the figure, the lever arm, l, is distance r from the hinge to the point at which you exert your force. The torque is the product of the magnitude of the perpendicular force multiplied by the lever arm.
Children normally need a certain number of calories each day (energy allowance) that their bodies use as energy for normal daily activities (walking, breathing, etc.). This ranges for boys from 2000 calories for a 7-10 year old, 2500 calories for an 11-14 year old, and 3000 calories for a 15-18 year old. For girls the ranges are from 2000 calories for a 7-10 year old, to 2200 calories for an 11-18 year old. These are only estimates and some children need more (fast metabolism) or less (slow metabolism) of an energy allowance for daily activities.
encouraging your 10 or 11 year old to eat a healthy diet can help him reach his full potential developmentally as well as prevent him from becoming overweight the dietary guidelines for americans 2010 report that about 32 percent of children and teens are overweight or obeseccording to the u s department of agriculture 10 to 11 year old boys need 1600 to 2200 calories a day while 10 to 11 year old girls usually require 1400 to 2000 calories a day to maintain a healthy weight the more active your child is the more calories he requires