Answer:
D) the sum of the kinetic energy and the internal energy is conserved
Explanation:
When soft deformable objects such as two balls of putty collide, their total energy will be conserved , according to law of conservation of energy .
Their energy involves kinetic energy and potential energy . Their kinetic energy is due to their motion . Their potential energy is due to their shape . If there is change in their shape , there will be change in their potential energy .
Their internal energy consists of potential energy and thermal energy . Due to collision , heat will be produced so their thermal energy will also change . In this way there will be change in their internal energy .
But in spite of all these changes , total energy will be conserved . That means if one form of energy is reduced , the other kind will be increased and so on.
Hence the sum of the kinetic energy and the internal energy is conserved
