Need help. How do i start the problem, thank you.

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AI Thread Summary
To solve the problem, first calculate the latent heat associated with the evaporation of 0.110 kg of water using the given latent heat value of 2.26 X 10^6 J/kg. This will provide the energy lost due to perspiration. Next, apply the first law of thermodynamics, ΔU = Q - W, where Q is the heat lost (latent heat) and W is the work done (2.43 X 10^5 J). Finally, determine the change in internal energy and convert the energy into nutritional calories. Understanding latent heat is crucial as it represents the energy change during phase transitions at constant temperature.
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Homework Statement



A basketball player does 2.43 X 105 J of work during her time in the game, and evaporates 0.110 kg of water. Assuming latent heat of 2.26 X 106 J/kg for the perspiration (the same as for water), (a) determine the change in the player’s internal energy, and (b) the number of nutritional calories the player has converted to work and heat.


Homework Equations


First law of thermodynamics
U = Q-W


The Attempt at a Solution


I need help on how to start it and what they mean by latent heat. Thank you
 
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The latent heat is the amount of energy absorbed or emitted by a system during a phase transition (liquid -> solid, say) carried out at constant temperature.

You should proceed in calculating what the latent heat is in this instance; then it should be fairly obvious what to do ;)


R.
 
just calculate net latent heat and this with the work done would be the net loss
 
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