Final answer:
The temperature needed for atoms to have an average kinetic energy of 6.40 × 10^-14 J in a fusion experiment is approximately 6164 K, thus the closest given option is (c) 8000 K.
Step-by-step explanation:
To determine the temperature needed for atoms in a fusion experiment to have average kinetic energies of 6.40 × 10-14 J, we use the fact that the average kinetic energy (KE) of particles is related to the absolute temperature (T) by the equation KE = (3/2) kT, where k is the Boltzmann constant (1.38 × 10-23 J/K). To solve for T, we rearrange the equation to T = (2/3) (KE/k) and substitute in the given kinetic energy value:
T = (2/3) (6.40 × 10-14 J) / (1.38 × 10-23 J/K)
Calculating this gives us a temperature of approximately 6164 K, which means the correct option is (c) 8000 K since it is the closest to our calculated value and the options provided are discretized rather than continuous values.