Question

The box of a well-known breakfast cereal states that one ounce of the cereal contains 113 calories (1 food calorie = 4186 j). If 1.79% 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 1.90 m?

Answer 1

Thus the weight of the heaviest particle is  m = 454.73 kg

Explanation:

To convert the energy of the cereal to know the weight:

m x g x h = Q'

Cal = 0.0179 x 113 Cal = 2.0227 Cal

Q' = 2.0227 Cal x 4186 J / 1 Cal

m x g x h = 8467.02 J

m x g = Q' / h = 8467.02 J / 1.90 m

m x g = 4456.33 N

Let's take the gravity as a g=9.8 m/s^2

m = 4456.33 N / 9.8 m/s^2

m = 454.73 kg

Thus the weight of the heaviest particle is  m = 454.73 kg