Partially correct answer. Your answer is partially correct. Try again. There are
ID: 1610375 • Letter: P
Question
Partially correct answer. Your answer is partially correct. Try again. There are Z protons in the nucleus of an atom, where Z is the atomic number of the element. An particle carries a charge of +2e. In a scattering experiment, an particle, heading directly toward a nucleus, will come to a halt when all the particle's kinetic energy is converted to electric potential energy. In such a situation, how close will an particle with a kinetic energy of 5.10 × 10-13 J come to a nucleus with atomic number Z = 85? Number Entry field with
incorrect answer -4.806e-14 Units Entry field with correct answer
Explanation / Answer
=8.854e-12 F/m, Ek=5e-13 J
Q=Zq, Q=2q, where q=1.6e-19 C is an elementary charge
Conservation of energy:
initial kinetic energy = final electrostatic potential energy
Ek=Ep=QQ/(4r)
r=QQ/(4Ek)
r=85*2*(1.6e-19)²/(4*8.854e-12*5.1e-13)
r=7.67e-14 m