n a running event, a sprinter does 5.5 105 J of work and her internal energy decreases by 8.8 105 J.
(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? select one
(i)There is no heat transferred between the sprinter and the environment.
ii) Energy is transferred from the sprinter to the environment by heat.
iii)Energy is transferred from the environment to the sprinter by heat.
a) We can use the first law of thermodynamics, which relates work, internal energy, and heat transfer:
ΔU = Q - W
where ΔU is the change in internal energy, Q is the heat transferred, and W is the work done.
We want to solve for Q, so we'll rearrange the equation:
Q = ΔU + W
Now, plug in the values:
Q = -8.8 * 10^5 J + 5.5 * 10^5 J = -3.3 * 10^5 J
So, the heat transferred between her body and surroundings during this event is -3.3 * 10^5 J.
b) Since the sign of the heat transfer is negative, this means that energy is transferred from the sprinter to the environment by heat. So the correct answer is (ii).
To determine the heat transferred between the sprinter and her surroundings during the event, we can use the principle of conservation of energy. According to this principle, the total energy transferred can be calculated by subtracting the work done by the sprinter from the change in her internal energy.
Given:
Work done by the sprinter = 5.5 x 10^5 J
Change in internal energy = -8.8 x 10^5 J
(a) Heat transferred between the sprinter and her surroundings:
Total energy transferred = Change in internal energy - Work done by the sprinter
Total energy transferred = (-8.8 x 10^5 J) - (5.5 x 10^5 J)
Total energy transferred = -14.3 x 10^5 J
Therefore, the heat transferred between the sprinter and her surroundings during the event is -14.3 x 10^5 J.
(b) The negative sign in the answer to part (a) indicates that energy is transferred from the sprinter to the environment by heat. So the correct choice is (ii) Energy is transferred from the sprinter to the environment by heat.
To determine the heat transferred between the sprinter's body and the surroundings during the event, we need to use the principle of the conservation of energy.
The principle states that the total energy of an isolated system remains constant. In this case, the sprinter's body and the surroundings can be considered as the isolated system. The energy can be transferred as work, heat, or changes in internal energy.
We are given that the sprinter does 5.5 * 10^5 J of work, and her internal energy decreases by 8.8 * 10^5 J.
(a) To find the heat transferred, we can use the equation:
Heat = Work + Change in Internal Energy
Heat = 5.5 * 10^5 J + (-8.8 * 10^5 J)
Heat = -3.3 * 10^5 J
Therefore, the heat transferred between the sprinter's body and the surroundings during this event is -3.3 * 10^5 J.
(b) The sign of the answer indicates the direction of energy transfer. In this case, since the heat transferred is negative, it means that energy is transferred from the sprinter to the surroundings by heat. Therefore, the correct answer is (ii) Energy is transferred from the sprinter to the environment by heat.