In a running event, a sprinter does 4.9 105 J of work and her internal energy decreases by 9.1 105 J.

Question

(a) Determine the heat transferred between her body and surroundings during this event.
J

(b) What does the sign of your answer to part (a) indicate?
There is no heat transferred between the sprinter and the environment. Energy is transferred from the environment to the sprinter by heat. Energy is transferred from the sprinter to the environment by heat.