Alice, whose mass is 55 kg, eats a jelly doughnut for breakfast. According to the nutrition label, the doughnut contains 540 Calories of energy. To “burn off" the doughnut, Alice decides to climb the stairs at her building. The height of a single stair is 15 cm. a) Suppose Alice's body is 100% efficient. This means that when her body produces 100 joules of energy, all 100 joules go into performing mechanical work, such as climbing stairs. With this assumption, how many stairs does Alice have to climb to burn off the doughnut? b) In reality, the human body is not 100% efficient. Suppose Alice's body is 25% efficient. This means that when her body produces 100 joules of energy, only 25 joules goes into performing mechanical work (such as climbing stairs) and the rest is used for internal energy (such as maintaining normal body temperature). With this assumption, how many stairs does Alice have to climb to burn off the doughnut?

Alice, whose mass is 55 kg, eats a jelly doughnut for breakfast. According to the nutrition label, the doughnut contains 540 Calories of energy. To “burn off" the doughnut, Alice decides to climb the stairs at her building. The height of a single stair is 15 cm. a) Suppose Alice's body is 100% efficient. This means that when her body produces 100 joules of energy, all 100 joules go into performing mechanical work, such as climbing stairs. With this assumption, how many stairs does Alice have to climb to burn off the doughnut? b) In reality, the human body is not 100% efficient. Suppose Alice's body is 25% efficient. This means that when her body produces 100 joules of energy, only 25 joules goes into performing mechanical work (such as climbing stairs) and the rest is used for internal energy (such as maintaining normal body temperature). With this assumption, how many stairs does Alice have to climb to burn off the doughnut?

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter11: Energy In Thermal Processes

Section: Chapter Questions

Problem 6P

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