# physics!

posted by .

while running a marathon, alex is producing about 900 calories per hour. 1 calorie is 4184 j. if the specific heat of the human body is 3500 j/kg x c, how many degrees celsius would alexs temperature increase if he did not sweat and ran the marathon in 3 h and 10 min? he has a mass of 75 kg.

thank god for sweat. if alex wants to release all of the caloric energy he produced so he doesnt heat up, how many litres of sweat would he need to produce and evaporate? the heat of vaporization for the water in sweat is 2.26 x 10^6 j/kg. the density of water is 1 g/ml

• physics! -

You are talking about kilocalories, not calories. (It is written as capitalized Calories when talking about nutrition and metabolic rates)

In a 3.17 hour race, the body heat generated will be
Q = 3.17h*900Cal/h*4184J/Cal = 1.19*10^7 Joules
Temperature would increase by
delta T = Q/M*C = 45.5 C

For the second question, divide Q by the heat of vaporization in J/kg. Then convert that mass to volume in liters, using the density.

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The text passage contains a physics problem related to heat and energy transfer in the human body during physical activity. It asks two specific questions: one about the temperature increase in the body due to heat production during a marathon, and another about the amount of sweat needed to evaporate to release the generated heat.
multiple_questions_with_answers

1. the first question asks how many degrees celsius alex's temperature would increase if he did not sweat and ran the marathon in 3 hours and 10 minutes. the answer provided is 45.5°c.
2. the second question asks how many liters of sweat alex would need to produce and evaporate to release all the caloric energy he produced. the solution is not fully provided, but the method to solve it is described.
Given a text passage, determine:
    1. If it contains a mathematical question (including word problems or calculations)
    2. If an answer to that mathematical question is provided in the text

First, describe the content structure you found in 1-2 sentences.

Then provide your analysis in the following format:
TYPE: <one of the following values>
- NO_QUESTION
- SINGLE_QUESTION
- SINGLE_QUESTION_WITH_ANSWER
- MULTIPLE_QUESTIONS
- MULTIPLE_QUESTIONS_WITH_ANSWERS
system
# physics!

posted by .

while running a marathon, alex is producing about 900 calories per hour. 1 calorie is 4184 j. if the specific heat of the human body is 3500 j/kg x c, how many degrees celsius would alexs temperature increase if he did not sweat and ran the marathon in 3 h and 10 min? he has a mass of 75 kg.

thank god for sweat. if alex wants to release all of the caloric energy he produced so he doesnt heat up, how many litres of sweat would he need to produce and evaporate? the heat of vaporization for the water in sweat is 2.26 x 10^6 j/kg. the density of water is 1 g/ml

• physics! -

You are talking about kilocalories, not calories. (It is written as capitalized Calories when talking about nutrition and metabolic rates)

In a 3.17 hour race, the body heat generated will be
Q = 3.17h*900Cal/h*4184J/Cal = 1.19*10^7 Joules
Temperature would increase by
delta T = Q/M*C = 45.5 C

For the second question, divide Q by the heat of vaporization in J/kg. Then convert that mass to volume in liters, using the density.

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1. ### science

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2. ### Physics Problem

While running, a 70.0 kg student generates thermal energy at a rate of 1200 W. To maintain a constant body temperature of 37.0 C, this energy must be removed by perspiration or other mechanisms. If these mechanisms failed and the heat …
3. ### Physics

If the air temperature is the same as the temperature of your skin (about 30 degrees Celcius), your body cannot get rid of heat by transferring it to the air. In that case, it gets rid of the heat by evaporating water (sweat). During …
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I'd love thorough solutions to these problems, but simply providing the specific formulas that I should solve each part of the problem with would be really good too. :-) Thanks! Human energetics You are sitting down to study in the …
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The basal metabolic rate is the rate at which energy is produced in the body when a person is at rest. A 70.0 kg person of height 1.79 m would have a body surface area of approximately 1.90 m^2. What is the net amount of heat this …
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During a dry day, a 70.0 kg athlete runs a marathon while the outside temperature is T2 = 33.2 ¢XC. The thermal power produced by the athlete's body is P = 1.05 ¡Ñ 103 W and the skin temperature is T3 = 35.5 ¢XC so that the themal …
7. ### Chemistry

How many joules (J) are needed to increase the temperature of15.0g of lead from 20 degrees celsius to 40 degrees celsius?
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water has a specific heat of 4184 j(kg K). How much energy is needed to increase the temperature of a kilogram of water 5 degrees celcius?
user
The text passage contains a physics problem related to heat and energy transfer in the human body during physical activity. It asks two specific questions: one about the temperature increase in the body due to heat production during a marathon, and another about the amount of sweat needed to evaporate to release the generated heat.

TYPE: MULTIPLE_QUESTIONS_WITH_ANSWERS

1. The first question asks how many degrees Celsius Alex's temperature would increase if he did not sweat and ran the marathon in 3 hours and 10 minutes. The answer provided is 45.5°C.
2. The second question asks how many liters of sweat Alex would need to produce and evaporate to release all the caloric energy he produced. The solution is not fully provided, but the method to solve it is described.