Concept explainers
(a)
The distance of the closest approach of alpha particle and a gold nucleus.
(a)
Answer to Problem 3P
The distance of the closest approach of alpha particle and a gold nucleus is
Explanation of Solution
On a head-on collision between an alpha particle and a gold nucleus
Write to formula for electrostatic potential energy
Write to formula for kinetic energy
Here,
Conclusion:
Here,
Substituting
Thus, the distance of the closest approach of alpha particle and a gold nucleus is
(b)
The initial minimum initial speed for an alpha particle to approach as closed as
(b)
Answer to Problem 3P
The initial minimum initial speed for an alpha particle to approach as closed as
Explanation of Solution
Consider the closed distance between the alpha particle and the gold nucleus is
Conclusion:
Equating (I) and (II),
Substituting
Thus, the initial minimum initial speed for an alpha particle to approach as closed as
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Chapter 44 Solutions
Bundle: Physics for Scientists and Engineers with Modern Physics, Loose-leaf Version, 9th + WebAssign Printed Access Card, Multi-Term
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- Each a particle in a beam of a particles has a kinetic energy of 4.5 MeV. Through what potential difference would you have to accelerate these a particles in order that they would have enough energy so that if one is fired head-on at a gold nucleus it could reach a point 1.9 10^-14 m from the center of the nucleus?arrow_forwardA beam of alpha particles is incident on a target of lead. A particular alpha particle comes in “head-on” to a particular lead nucleu and stops 6.50 * 10-14 m away from the center of the nucleus. (This point is well outside the nucleus.) Assume that the lead nucleus, which has 82 protons, remains at rest. The mass of the alpha particle is 6.64 * 10-27 kg. (a) Calculate the electrostatic potential energy at the instant that the alpha particle stops. Express your result in joules and in MeV. (b) What initial kinetic energy (in joules and in MeV) did the alpha particle have? (c) What was the initial speed of the alpha particle?arrow_forwardWhen an alpha particle collides elastically with a nucleus, the nucleus recoils. Suppose a 5.00 MeV alpha particle has a headon elastic collision with a gold nucleus that is initially at rest.What is the kinetic energy of (a) the recoiling nucleus and (b) the rebounding alpha particle?arrow_forward
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