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In a running event, a sprinter does 4.8 x 10⁵ j of work and her internal energy decreases by 7.5×10⁵ j.

determine the heat transferred between her body and surroundings during this event.

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Final answer:

The heat transferred from the sprinter's body to the surroundings during the event is -2.7 x 10^5 J, as calculated using the first law of thermodynamics.

Step-by-step explanation:

The question is about the calculation of heat transfer in a physical process, using the first law of thermodynamics. The first law of thermodynamics relates the change in internal energy (\( \Delta U \)) of a system to the heat transfer (\( Q \)) to and from the system and the work (\( W \)) done by or on the system. It is given by the equation:

\[ \Delta U = Q - W \]

For the sprinter, we know the work done (\( W = 4.8 \times 10^5 \, \text{J} \)) and the change in internal energy (\( \Delta U = -7.5 \times 10^5 \, \text{J} \)). The negative sign indicates a decrease in internal energy. To find the heat transfer, we rearrange the first law of thermodynamics as follows:

\[ Q = \Delta U + W \]

Substituting the given values:

\[ Q = (-7.5 \times 10^5 \, \text{J}) + (4.8 \times 10^5 \, \text{J}) \]

\[ Q = -2.7 \times 10^5 \, \text{J} \]

The negative sign of \( Q \) indicates that heat is transferred from the sprinter's body to the surroundings. Therefore, during the event, the heat transferred from the sprinter's body to the surroundings is \( -2.7 \times 10^5 \, \text{J} \).

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