1. A 53-kg woman cheats on her diet and eats a 588-Calorie (588 kcal) jelly doughnut for breakfast.(a) How many joules of energy are the equivalent of one jelly doughnut? .........J (b) How many stairs must the woman climb to perform an amount of mechanical work equivalent to the food energy in one jelly doughnut? Assume the height of a single stair is 15 cm. stairs (c) If the human body is only 23% efficient in converting chemical energy to mechanical energy, how many stairs must the woman climb to work off her breakfast? stairs

2. Lead pellets, each of mass1.00g, are heated to 200C. How many pellets must be added to530g of water that is initially at 20.0C to make the equilibrium temperature 25.0C?

Neglect any energy transfer to or from the container. My answer was 467 but that is wrong Your response is within 10% of the correct value. This may be due to roundoff error, or you could have a mistake in your calculation. Carry out all intermediate results to at least four-digit accuracy to minimize roundoff error.pellets

3. When you jog, most of the food energy you burn above your basal metabolic rate (BMR) ends up as internal energy that would raise your body temperature if it were not eliminated. The evaporation of perspiration is the primary mechanism for eliminating this energy. Determine the amount of water you lose to evaporation when running for26minutes at a rate that uses 400 kcal/h above your BMR. (That amount is often considered to be the "maximum fat-burning" energy output.) ...... kg The metabolism of 1 gram of fat generates approximately9.3kcal of energy and produces approximately 1 gram of water. (The hydrogen atoms in the fat molecule are transferred to oxygen to form water.) What fraction of your need for water will be provided by fat metabolism? (The latent heat of vaporization of water at room temperature is2.510⁶J/kg.) ....... %