an alpha particle is
a helium nucleus
a beta particle is
an electron
gamma ray is
a photon
the operation of a cloud chamber does not rely on
evaporation
when a beta particle is ejected from a nucleus, the nucleus then has a slightly
smaller mass and significantly greater charge
different isotopes of an element have different numbers of
....none of these
when thorium (A=90) emits a beta particle, the resulting nucleus has atomic number
none of the these
most of the radioactivity from man-made sources that we personally encounter comes from
medical xrays
carbon dating requires that the object being tested contain
organic material
which of the following are beneficial applications of radioactivity
irradiation of the food supply, radioactive tracers in crop fertilizer, strong doses of radioactivity for cancer treatment
the half-life on an isotope is two days, at the end of four days how much of the isotope remains?
one-quarter
the main influence working to hold nuclei together is the ____ and a main influence working to break them apart is the________
strong force; electromagnetic force
in the fissioning of uranium, a chain reaction is caused by
ejected neutrons
if lead were used as nuclear fuel, it would be best
fissioned
control is exercised in a nuclear reactor by
absorbing excess neutrons with control rods
a nuclear process that has relatively few radio-active by products is
fusion
according to Einstein's theory of special relativity
A) energy and mass are aspects of each other
B) space and time are aspects of each other
BOTH OF THESE
a spaceship that is traveling at 0.5 c with respect to your frame of reference, fires a photon beam that travels at speed c with a respect to the spaceship. you measure the photon beam's speed to be
equal to c
according to the special theory of relativity, all laws of nature are the same for the 'special' case of reference that
move at constant velocity
event A occurs before event B in a certain frame of reference. in another frame of reference event A could occur
after even B, simultaneous with even B
compared to clocks in a stationary reference frame, clocks in a moving reference frame run
slower
there is an upper limit on the speed of a particle. this means there is also an upper limit on its
neither momentum or kinetic energy
consider a spaceship that moves toward you at 0.3c (three-tenths the speed of light) it fires a probe toward you, relative to itself, at 0.3c. relative to you, the probe approaches at about
0.55c
parents can be biologically younger than their children if
the parents take a fast round trip space trip
according to special relativity, one can travel at increased rates
only forward in time
the length of a meterstick projected like a spear at 0.87c is seen by a person at rest to be about
0.5m
compared to a special relativity, general relativity is more concerned with
acceleration, gravitation, and space-time geometry
light bends when it
passes a massive star, passes through a gravitational field
in a one-g gravitational field, in one second, a light beam will curve beneath a perfectly straight line by
4.9 m
from a general relativistic point of view, a person on the ground floor of a skyscraper ages
slower than a person on the top floor
space in the local area around a star is
closed, or sphere-shaped