Physics
posted by Anonymous on .
The box of a wellknown breakfast cereal states that one ounce of the cereal contains 129 Calories (1 food Calorie = 4186 J). If 2.55% of this energy could be converted by a weight lifter's body into work done in lifting a barbell, what is the weight of the heaviest barbell that could be lifted a distance of 1.91 m?

129 Cal * 4186 J/Cal = 536,124 Joules
.0255 * 536,124 = 13,671 Joules
m g h = m g (1.91) = 13,671
so
m g = 7158 Newtons weight
and
m = 730 Kilograms of mass
around 1600 pounds