Question

The energy transfer diagram represents the energy of a person diving into a pool. A wide arrow labeled gravitational potential energy 8000 J with a small arrow turning away from it labeled thermal energy ? J. The rest of the arrow goes forward labeled kinetic energy 7000 J. How much thermal energy is generated? 1000 J 2000 J 7000 J 15,000 J

Answer 1

1000J

Explanation:

EDGE2020

Answer 2

The amount of thermal energy that is generated is 1000 joules.

Explanation:

Let consider the person diving into a pool as a closed system, that is, a system with only energy interaction with the surroundings. According to the First Law of Thermodynamics, which is a generalization of the Principle of Energy Conservation, the total energy of the system is neither destroyed, nor created, only transformed. The initial gravitational potential energy is transformed into translational kinetic and thermal energy. That is to say:

`U_(g) - K - Q = 0`

Where:

`U_(g)` - Gravitational potential energy, measured in joules.

`K_(tr)` - Translational kinetic energy, measured in joules.

`Q` - Thermal energy, measured in joules.

The thermal energy is now cleared:

`Q = U_(g)-K`

Given that
`U_(g) = 8000\,J` and
`K = 7000\,J`, the amount of thermal energy that is generated is:

`Q = 8000\,J - 7000\,J`

`Q = 1000\,J`

The amount of thermal energy that is generated is 1000 joules.