Chapter 4

Question 1

Energy in the Sun is produced primarily by

a. fossil fuels
b. neutrinos
c. fission
d. fusion

Answer 1

d. fusion

Question 2

The mass of the nucleus is closet to

a. 99% of that in the entire atom
b. 1% of that in the atom
c. 10^-5 of that in the atom
d. 10 ^-15 of that in the atom

Answer 2

a. 99% of that in the entire atom

Question 3

Radioactivity in the Earth leads to

a. energy for volcanoes
b. helium for toy balloons
c. heat for geysers
d. all of the above

Answer 3

d. all of the above

Question 4

LD50 Refers to a

a. lethal dose
b. legal dose
c. large dose
d. lowest dose

Answer 4

a. lethal dose

Question 5

A major reason that your body is radioactive is that

a. it is slightly contaminated by debris from nuclear tests
b. it is made radioactive by medical x-rays
c. you eat radioactive carbon in your food
d. you are hit by neutrinos from the sun

Answer 5

c. you eat radioactive carbon in your food

Question 6

The primary cause of death from the Hiroshima bomb was

a. radiation-induced cancer
b. the blast from the bomb
c. fallout from the bomb
d. smoking induced by fear of the bomb

Answer 6

b. the blast from the bomb

Question 7

Fission fragments are

a. harmless particles emitted in radioactivity
b. among the most dangerous kind of radiation
c. ghost-like particles that pass through the Earth
d. the source of most energy in the Sun

Answer 7

b. among the most dangerous kind of radiation

Question 8

Wine made from fossil fuels is not radioactive because

a. the radioactivity has decayed away
b. there is no carbon in such wine
c. ancient plants never were radioactive
d. the half-life of the key elements is too long

Answer 8

a. the radioactivity has decayed away

Question 9

If the half-life of an element is big, that means that

a. It decays faster than one with a small half-life
b. it decays slower than one with a small half-life
c. it belongs to a very heavy element
d. it emits lots of neutrons when it decays

Answer 9

b. it decays slower than one with a small half-life

Question 10

Muller wears a wristwatch with tritium in the watch hands because

a. he is not worried about radioactivity
b. tritium is not radioactive
c. the levels of radiation that emerge are safe
d. no radiation emerges from the watch hands

Answer 10

d. no radiation emerges from the watch hands

Question 11

After three half-lives, the fraction of nuclei remaining is

a. 1/2
b. 1/3
c. 1/4
d. 1/8

Answer 11

d. 1/8

Question 12

Most of the elements found on the Earth were created

a. in the first few million years of the Earth’s existence
b. with in a star
c. in the Big Bang
d. in a supernova explosion

Answer 12

b. with in a star

Question 13

The fraction of the U.S. population that dies from cancer is typically

a. about 1 in 10,000
b. about 1 in 100
c. about 1 in 5
d. most of us die from cancer.

Answer 13

c. about 1 in 5

Question 14

Watch dials containing radium glow because

a. all radioactivity creates light
b. batteries supply energy when a button is pushed
c. the radiation hits a phosphor
d. They don’t glow. Only tritium glows.

Answer 14

c. the radiation hits a phosphor

Question 15

Choose all the items that derive from radioactivity:

a. Helium for children’s balloons
b. Volcanic lava
c. Warmth in deep mines
d. most cancer in the United States

Answer 15

a. Helium for children’s balloons
b. Volcanic lava
c. Warmth in deep mines

Question 16

After four half-lives, the surviving tritium atoms are removed. Compared to completely new tritium atoms, they are expected to live

a. 1/8 as long
b. 1/4 as long
c. 1/2 as long
d. exactly as long

Answer 16

d. exactly as long

Question 17

One rem of radiation dose takes how many gammas per square centimeter?

a. about 1
b. about 5000
c. about a million
d. about 2,000,000,000

Answer 17

d. about 2,000,000,000

Question 18

Which requires the larger dose?

a. radiation poisoning
b. cancer
c. they are very close in amount needed.

Answer 18

b. cancer

Question 19

The linear hypothesis is (Choose all that are correct)

a. known to be true
b. widely used even though it is not proven
c. known to be false
d. generally ignored in analysis of radiation deaths

Answer 19

b. widely used even though it is not proven

Question 20

A Sievert is how many rem?

a. 1
b. 0.01
c. 100
d. 1000

Answer 20

c. 100

Question 21

Cancer is lower in Denver because

a. the radiation is lower
b. the radiation is higher
c. there are more gamma rays even though there are fewer betas
d. We don’t know why.

Answer 21

d. We don’t know why.

Question 22

The number of deaths from the Chernobyl accident is about

a. less than 1
b. 24,000
c. 124,000
d. over a million

Answer 22

b. 24,000

Question 23

Radioactivity is used in

a. flashlights
b. TV screens
c. fluorescent lights
d. smoke detectors

Answer 23

d. smoke detectors

Question 24

Neutron activation is used

a. to treat cancer
b. to search for rare atoms
c. to provide energy
d. to create light

Answer 24

b. to search for rare atoms

Question 25

Dirty bombs may be less of a threat that people fear, because a. once spread out, the rem level drops below the radiation illness threshold b. dirty bombs require plutonium, and that is hard for terrorists to obtain c. the radioactivity is too small to induce cancer d. the radiation does not actually get out of the bomb case, even when exploded

Answer 25

a. once spread out, the rem level drops below the radiation illness threshold

Question 26

Radioactivity in the Earth is responsible for a. helium we use in balloons b. warmth to keep the oceans liquid c. creation of the oxygen we breathe d. navigation of birds

Answer 26

a. helium we use in balloons

Question 27

Volcanic heat comes from a. radioactive explosions b. the weight of rock c. accumulated sunlight d. fusion deep in the Earth

Answer 27

a. radioactive explosions

Question 28

The best way to measure the age of an ancient bone is a. potassium-argon dating b. neutron activation c. controlled thermonuclear fusion d. radiocarbon dating

Answer 28

d. radiocarbon dating

Question 29

An RTG (radioisotope thermoelectric generator) is a. a type of bomb b. used in hospitals for power c. carried in pacemakers to supply power d. carried in satellites for power

Answer 29

d. carried in satellites for power

Question 30

Uranium is found on the Earth, even though it is radioactive. That's because a it is constantly made by cosmic rays b. it has a very long half-life c. it is created in fusion in the sun d. it is created by fusion in the Earth

Answer 30

b. it has a very long half-life

Question 31

Carbon-14, compared to carbon-12, a. has more protons b. has more neutrons c. has more electrons d. has a shorter half-life

Answer 31

b. has more neutrons

Question 32

Alexander Litvinenko was assassinated with a. plutonium b. tritium c. radium d. polonium

Answer 32

d. polonium

Question 33

The radiation from cell phones a. does not cause cancer b. causes cancer, but not enough to worry c. causes over 1% of the cancer in those who use them d. protects users from cosmic rays

Answer 33

a. does not cause cancer

Question 34

The threshold for radiation illness is about a. 1 rem b. 100 rem c. 500 rem d. 2500 rem

Answer 34

b. 100 rem

Question 35

The natural radioactivity (rate of nuclear decays) in a typical human body is closet to a. 0.2 per hour b. 12 per hour c. 12 per minute d. 4000 per second

Answer 35

d. 4000 per second

Question 36

Which of the following is most toxic per gram? a. arsenic b. botox c. water d. plutonium

Answer 36

b. botox

Question 37

The radioactivity from your own body a. does not cause cancer because it is natural b. is responsible for more than half of the cancer in humans c. does cause cancer, but at a very low rate d. helps reduce natural cancer, just as radiation therapy does

Answer 37

c. does cause cancer, but at a very low rate

Question 38

The source of energy in the Sun is a. uranium chain reaction b. radioactivity of tritium c. fusion of hydrogen d. radioactivity of potassium-40

Answer 38

c. fusion of hydrogen

Question 39

Drinking alcohol is required to be radioactive because a. it proves that it is not made of petroleum b. it is healthier c. it shows that alcohol was 'aged' d. it is not required; just the opposite, alcohol for consumption must not be radioactive.

Answer 39

a. it proves that it is not made of petroleum