A van is traveling at a constant speed of 54km. h^-1 in a 40km. h^-1 and the policeman starts his car from rest just as the van passes him. the police car accelerates at 2m. s^-2 until it reaches a maximum velocity of 20m. s^-1. Which vehicle between the van and police car will be ahead at the time of 10m. s^

Which of the following best describes internal energy? a. the difference between the kinetic and potential energies of the particles in a system b. the sum of the kinetic and potential energies of the particles in a system c. the sum of the kinetic and thermal energies of the particles in a system d. the difference between the kinetic and thermal energies of the particles in a system