Conceptual Physics

Chapter 38 Problems

Conceptual Problems

C.1 In Rutherford's scattering experiment, positive alpha particles are directed at a thin gold foil. What was the key piece of
evidence that led him to conclude that the positive charge and mass of the atom were concentrated in the nucleus?

i. All the alpha particles bounced straight back from the gold foil.

ii. None of the alpha particles were deflected by the gold foil.

iii. A small fraction were deflected from the gold foil.

iv. The alpha particles were absorbed by the gold foil.

C.2 What is the approximate ratio between an atomic diameter and a nuclear diameter?

i. 1:1

ii. 10:1

iii. 100:1

iv. 10000:1

C.3 Consider the following atoms:^12 C,^14 C,^14 N,^14 O,^16 O. The atomic numbers of carbon, nitrogen, and oxygen are 6, 7, and 8,

respectively.

(a) Which atoms are isotopes of each other? Check all that apply.

(b) Which atoms have the same number of neutrons? Check all that apply.

(c) Which atoms have the same number of protons? Check all that apply.

(a)^12 C and^14 C

(^14) C and (^14) N and (^14) O
(^14) O and (^16) O
none of them
(b)^12 C and^14 C
(^12) C and (^14) O
(^14) C and (^16) O
(^12) C and (^14) N
none of them
(c)^12 C and^14 C
(^14) C and (^14) N and (^14) O
(^14) O and (^16) O
none of them
C.4 The strong force acts between which of the following types of particles? Check all that apply.
proton and neutron
proton and proton
proton and electron
neutron and neutron
neutron and electron
C.5 What force or forces are responsible for keeping electrons in their orbits around the nucleus?
i. Strong force
ii. Electric (Coulomb) attraction
iii. Strong force and Coulomb attraction
iv. None of these
C.6 Consider the following atoms:^12 C,^14 C,^16 O. Rank these in order, from smallest to largest nuclear radii.
(^12) C (^14) C (^16) O
(^12) C (^16) O (^14) C
(^14) C (^12) C (^16) O
(^14) C (^16) O (^12) C
(^16) O (^12) C (^14) C
(^16) O (^14) C (^12) C
C.7 Can two iron atoms fuse to form a nucleus with greater binding energy per nucleon? Explain your answer.
Yes No
C.8 Explain in your own words why a chain reaction is possible during uranium fission.

Copyright 2000-2007 Kinetic Books Co. Chapter 38 Problems^717