A wire 12.0 m long and having a mass of 90 g is stretched under a tension of 240 N. A pulse is sent from the left end of the string, and 20 ms later another pulse is sent in the opposite direction from the right end of the string. How far from the left end of the string do the pulses first meet

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