In a Head-On Collision, an Alpha Particle (Z = 2)of $8.20 \mathrm { MeV }$

question 48

Multiple Choice

In a head-on collision, an alpha particle (Z = 2) of energy $8.20 \mathrm { MeV }$ bounces straight back from a nucleus of charge $80.0 \mathrm { e. }$ How close were the centers of the objects at closest approach? (1 eV = 1.60 × 10^-19 J, e = 1.60 × 10^-19 C, 1/4??₀ = 8.99 × 10⁹ N ? m²/C²)

• A)2.81 × 10^-14 m
• B)3.39 × 10^-12 m
• C)6.56 × 10^-15 m
• D)2.17 × 10^-14 m

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