Environmental Engineering Reference
In-Depth Information
0.005
0.004
0.003
0.002
0.001
0.000
0.0
0.2
0.4
0.6
0.8 1.0
1 − cos q
1.2
1.4
1.6
1.8
2.0
Figure 7.6 Comparison of Compton's original data with the theoretical expectations. From
A.H. Compton, Phys. Rev. 21 (1923) 483.
7.2 What is the speed of a particle whose kinetic energy is equal to (a) its rest
energy; (b) five times its rest energy?
7.3 The Sun produces energy at a rate of 3
.
8
10
26
×
W. How much mass does
the Sun lose each second?
7.4 Calculate the speed of an electron of kinetic energy equal to 0.1 MeV accord-
ing to both classical and relativistic mechanics. [The mass of an electron is
0.511 MeV/
c
2
.]
7.5 A particle with momentum 6.0 GeV/
c
has a total energy of 11.2 GeV. Deter-
mine the mass of the particle and its speed.
7.6 What is the total energy of a particle of mass 80 GeV/
c
2
which has momentum
65 GeV/
c
? What is its kinetic energy? Is the particle relativistic or not?
7.7 Two deuterium nuclei can fuse together to form one helium nucleus. The mass
of a deuterium nucleus is 2
.
0136
u
and that of a helium nucleus is 4
.
0015
u
(
u
is the atomic mass unit).
(a) How much energy is released when 1 kg of deuterium undergoes fusion?
(b) The annual consumption of electrical energy in the USA is of order 10
20
J.
How much deuterium must react to produce this much energy?
7.8 A (fictitious) particle of mass 1 MeV/
c
2
and kinetic energy 2 MeV collides
with a stationary particle of mass 2 MeV/
c
2
. After the collision, the particles
form a new particle. Find
(a) the speed of the first particle before the collision;
(b) the total energy of the first particle before the collision;
(c) the initial total momentum of the system;
(d) the mass of the system after the collision;
(e) the total kinetic energy after the collision.