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Clicker Questions

ConcepTests

Chapter 32

Physics, 3rd Edition

James S. Walker

ConcepTest 32.1 ConcepTest 32.1 The NucleusThe Nucleus

There are 82 protons in a lead nucleus. Why doesn’t the lead nucleus burst apart?

1) Coulomb repulsive force doesn’t act 1) Coulomb repulsive force doesn’t act inside the nucleusinside the nucleus

2) gravity overpowers the Coulomb 2) gravity overpowers the Coulomb repulsive force inside the nucleusrepulsive force inside the nucleus

3) the negatively charged neutrons balance 3) the negatively charged neutrons balance the positively charged protonsthe positively charged protons

4) protons lose their positive charge4) protons lose their positive chargeinside the nucleusinside the nucleus

5) none of the above5) none of the above

The Coulomb repulsive force is overcome by the even stronger nuclear forcenuclear force!

ConcepTest 32.1 ConcepTest 32.1 The NucleusThe Nucleus

There are 82 protons in a lead nucleus. Why doesn’t the lead nucleus burst apart?

1) Coulomb repulsive force doesn’t act 1) Coulomb repulsive force doesn’t act inside the nucleusinside the nucleus

2) gravity overpowers the Coulomb 2) gravity overpowers the Coulomb repulsive force inside the nucleusrepulsive force inside the nucleus

3) the negatively charged neutrons balance 3) the negatively charged neutrons balance the positively charged protonsthe positively charged protons

4) protons lose their positive charge4) protons lose their positive chargeinside the nucleusinside the nucleus

5) none of the above5) none of the above

What weighs more, an electron and a proton, or a hydrogen atom?

1) electron and proton1) electron and proton

2) hydrogen atom 2) hydrogen atom

3) both the same3) both the same

ConcepTest 32.2a ConcepTest 32.2a Binding Energy IBinding Energy I

What weighs more, an electron and a proton, or a hydrogen atom?

1) electron and proton1) electron and proton

2) hydrogen atom 2) hydrogen atom

3) both the same3) both the same

ConcepTest 32.2a ConcepTest 32.2a Binding Energy IBinding Energy I

The total energy (or mass) of a hydrogen atom must be lessless than the energies (or masses) of the electron plus the proton individually in order for the electron to be bound.

ConcepTest 32.2b ConcepTest 32.2b Binding Energy IIBinding Energy II

What is the total energy

(or mass) of the hydrogen

atom in its ground state?

1) 13.6 eV1) 13.6 eV

2) 2) mmppcc22 + + mmeecc22 + 13.6 eV + 13.6 eV

3) 3) mmppcc22 + + mmeecc22

4) 4) mmppcc22 + + mmeecc22 – 13.6 eV – 13.6 eV

The total energy (or mass) of a hydrogen atom must be lessless than the energies (or masses) of the electron plus the proton individually in order for the electron to be bound. The mass difference is The mass difference is the binding energy.the binding energy.

ConcepTest 32.2b ConcepTest 32.2b Binding Energy IIBinding Energy II

What is the total energy

(or mass) of the hydrogen

atom in its ground state?

1) 13.6 eV1) 13.6 eV

2) 2) mmppcc22 + + mmeecc22 + 13.6 eV + 13.6 eV

3) 3) mmppcc22 + + mmeecc22

4) 4) mmppcc22 + + mmeecc22 – 13.6 eV – 13.6 eV

1) the 2 neutrons and 1 proton2) the tritium nucleus3) they both weigh the same4) it depends on the specific isotope of tritium

On a balance scale, you put 2 neutrons and 1 proton on one side and you put a tritium nucleus (3H) on the other. Which side weighs more?

ConcepTest 32.2c ConcepTest 32.2c Binding Energy IIIBinding Energy III

The mass of the 2 neutrons and 1 proton is lessless when they are bound together as tritium. The The mass difference is the binding mass difference is the binding energy.energy.

need to need to addadd 8.5 MeV8.5 MeV to balance scaleto balance scale

1) the 2 neutrons and 1 proton2) the tritium nucleus3) they both weigh the same4) it depends on the specific

isotope of tritium

On a balance scale, you put 2 neutrons and 1 proton on one side and you put a tritium nucleus (3H) on the other. Which side weighs more?

ConcepTest 32.2c ConcepTest 32.2c Binding Energy IIIBinding Energy III

1) removing a proton takes more energy2) removing a neutron takes more energy3) both take the same amount of energy

Does it take more energy to remove one proton or one neutron from 16O?

ConcepTest 32.3 ConcepTest 32.3 Separation EnergySeparation Energy

Removing a proton takes lessless energy because the repulsive Coulomb forcerepulsive Coulomb force between positively charged protons helps to push the proton out of the nucleus. Remember that neutrons are uncharged.

1) removing a proton takes more energy2) removing a neutron takes more energy3) both take the same amount of energy

Does it take more energy to remove one proton or one neutron from 16O?

ConcepTest 32.3 ConcepTest 32.3 Separation EnergySeparation Energy

ConcepTest 32.4 ConcepTest 32.4 Nuclear Reaction ProductsNuclear Reaction Products

What is the nucleus that results in the reaction given below?

n O H 816

12?

O178

O157

N157

F157

1) 1)

2) 2)

3) 3)

4) 4)

XXAAZZ

Add up the totals for nucleons (A) and protons (Z) separately, and see what you need to balance both sides:

Nucleons: 1 + 16 = Nucleons: 1 + 16 = xx + 2 + 2 xx = 15 = 15Protons: 0 + 8 = Protons: 0 + 8 = yy + 1 + 1 yy = 7 = 7The missing nucleus has The missing nucleus has AA = 15 and = 15 and ZZ = 7. = 7.

ConcepTest 32.4 ConcepTest 32.4 Nuclear Reaction ProductsNuclear Reaction Products

What is the nucleus that results in the reaction given below?

n O H 816

12?

O178

O157

N157

F157

1) 1)

2) 2)

3) 3)

4) 4)

XXAAZZFollow-up:Follow-up: What would you get if you started with What would you get if you started with pp + + 1616OO instead? instead?

What is the Q-value for radioactive decay reactions?

1) 1) QQ < 0 < 02) 2) QQ > 0 > 03) 3) QQ = 0 = 04) sign of 4) sign of QQ depends on the nucleus depends on the nucleus

ConcepTest 32.5 ConcepTest 32.5 Nuclear ReactionsNuclear Reactions

Radioactive decay happens spontaneouslyspontaneously,

because the nucleus can reach a lower energy

state. Thus, such reactions can only occur

spontaneously if they releaserelease energyenergy

(exothermicexothermic ), so the QQ-value is positive-value is positive.

What is the Q-value for radioactive decay reactions?

1) 1) QQ < 0 < 02) 2) QQ > 0 > 03) 3) QQ = 0 = 04) sign of 4) sign of QQ depends on the nucleus depends on the nucleus

ConcepTest 32.5 ConcepTest 32.5 Nuclear ReactionsNuclear Reactions

Follow-up:Follow-up: Is radioactive decay an endothermic or exothermic reaction? Is radioactive decay an endothermic or exothermic reaction?

A radioactive substance decays and the emitted particle passes through a uniform magnetic field pointing into the page as shown. In which direction are alpha particles deflected?

B field

source

ConcepTest 32.6a ConcepTest 32.6a Particle Emission IParticle Emission I

Using the right-hand rule, we find that positivelypositively charged particles (alpha particlesalpha particles) are deflected to the leftto the left.

A radioactive substance decays and the emitted particle passes through a uniform magnetic field pointing into the page as shown. In which direction are alpha particles deflected?

B field

source

ConcepTest 32.6a ConcepTest 32.6a Particle Emission IParticle Emission I

A radioactive substance decays and the emitted particle passes through a uniform magnetic field pointing into the page as shown. In which direction are gamma rays deflected?

B field

source

ConcepTest 32.6b ConcepTest 32.6b Particle Emission IIParticle Emission II

Gamma rays are unchargeduncharged, so they will not be deflectednot be deflected by a magnetic field.

A radioactive substance decays and the emitted particle passes through a uniform magnetic field pointing into the page as shown. In which direction are gamma rays deflected?

B field

source

ConcepTest 32.6b ConcepTest 32.6b Particle Emission IIParticle Emission II

Follow-up:Follow-up: What particles are bent to the right? What particles are bent to the right?

A radioactive nucleus undergoes gamma decay. How large would you expect the energy of the emitted photon to be?

1) less than 13.6 eV1) less than 13.6 eV2) 13.6 eV2) 13.6 eV3) hundreds of eV3) hundreds of eV4) millions of eV4) millions of eV5) billions of eV5) billions of eV

ConcepTest 32.7 ConcepTest 32.7 Radioactive Decay EnergyRadioactive Decay Energy

The binding energy of nuclei is of the order several MeVseveral MeV (millions of eV). So, we would expect the energy of gamma decay to be in the same ballpark.

A radioactive nucleus undergoes gamma decay. How large would you expect the energy of the emitted photon to be?

1) less than 13.6 eV1) less than 13.6 eV2) 13.6 eV2) 13.6 eV3) hundreds of eV3) hundreds of eV4) millions of eV4) millions of eV5) billions of eV5) billions of eV

ConcepTest 32.7 ConcepTest 32.7 Radioactive Decay EnergyRadioactive Decay Energy

Follow-up:Follow-up: What process could release a photon with billions of What process could release a photon with billions of eV?eV?

1) the 1) the 234234Th nucleusTh nucleus

2) the alpha particle2) the alpha particle

3) both the same3) both the same

A uranium nucleus 238U (initially at rest) decays into a thorium nucleus 234Th and an alpha particle. Which one has the greater momentum?

ConcepTest 32.8a ConcepTest 32.8a Alpha Decay IAlpha Decay I

By momentum conservation, they must have the samesame magnitude of momentum since the initial momentum was zeroinitial momentum was zero.

1) the 1) the 234234Th nucleusTh nucleus

2) the alpha particle2) the alpha particle

3) both the same3) both the same

A uranium nucleus 238U (initially at rest) decays into a thorium nucleus 234Th and an alpha particle. Which one has the greater momentum?

ConcepTest 32.8a ConcepTest 32.8a Alpha Decay IAlpha Decay I

Follow-up:Follow-up: In what directions are the two products emitted? In what directions are the two products emitted?

1) the 1) the 234234Th nucleusTh nucleus

2) the alpha particle2) the alpha particle

3) both the same3) both the same

ConcepTest 32.8b ConcepTest 32.8b Alpha Decay IIAlpha Decay II

A uranium nucleus 238U (initially at rest) decays into a thorium nucleus 234Th and an alpha particle. Which one has the greater velocity?

1) the 1) the 234234Th nucleusTh nucleus

2) the alpha particle2) the alpha particle

3) both the same3) both the same

The momentum is mv and is thethe samesame for both, but the alpha particle has the smaller smaller massmass, so it has the larger velocitylarger velocity.

ConcepTest 32.8b ConcepTest 32.8b Alpha Decay IIAlpha Decay II

A uranium nucleus 238U (initially at rest) decays into a thorium nucleus 234Th and an alpha particle. Which one has the greater velocity?

1) the 1) the 234234Th nucleusTh nucleus

2) the alpha particle2) the alpha particle

3) both the same3) both the same

ConcepTest 32.8c ConcepTest 32.8c Alpha Decay IIIAlpha Decay III

A uranium nucleus 238U (initially at rest) decays into a thorium nucleus 234Th and an alpha particle. Which one has the greater kinetic energy?

1) the 1) the 234234Th nucleusTh nucleus

2) the alpha particle2) the alpha particle

3) both the same3) both the same

The kinetic energy 1/2 mv2 can be written as KE = p2/2m. The momentum is themomentum is the samesame for both, but the alpha particle has the smaller smaller massmass, so it has the larger KElarger KE.

ConcepTest 32.8c ConcepTest 32.8c Alpha Decay IIIAlpha Decay III

A uranium nucleus 238U (initially at rest) decays into a thorium nucleus 234Th and an alpha particle. Which one has the greater kinetic energy?

What element results when 14C undergoes beta decay?

1) 1) 15C

2) 2) 15N

3) 3) 14C

4) 14N

5) 15O

ConcepTest 32.9 ConcepTest 32.9 Beta DecayBeta Decay

The reaction is: neutrinoeNC 147

146

What element results when 14C undergoes beta decay?

1) 1) 15C

2) 2) 15N

3) 3) 14C

4) 14N

5) 15O

Inside the nucleus, the reaction n n p + e p + e-- + + has occurred, changing a neutron into a protonchanging a neutron into a proton, so the atomic number Z increases by 1Z increases by 1. However the mass number (A = 14) stays the same.

ConcepTest 32.9 ConcepTest 32.9 Beta DecayBeta Decay

Follow-up:Follow-up: How would you turn How would you turn 1414C into C into 1515N?N?

You have 16 kg of a radioactive sample with a certain half-life of 30 years. How much is left after 90 years?

1) 1) 8 kg8 kg

2) 2) 4 kg4 kg

3) 3) 2 kg2 kg

4) 4) 1 kg1 kg

5) 5) nothingnothing

ConcepTest 32.10a ConcepTest 32.10a Radioactive Decay Law IRadioactive Decay Law I

The total time (90 years90 years) is 3 half-lives3 half-lives. After one half-life 8 kg left. After two half-lives 4 kg left. After After three half-lives three half-lives 2 kg left 2 kg left.

You have 16 kg of a radioactive sample with a certain half-life of 30 years. How much is left after 90 years?

1) 1) 8 kg8 kg

2) 2) 4 kg4 kg

3) 3) 2 kg2 kg

4) 4) 1 kg1 kg

5) 5) nothingnothing

ConcepTest 32.10a ConcepTest 32.10a Radioactive Decay Law IRadioactive Decay Law I

Follow-up:Follow-up: When will the sample be reduced to nothing? When will the sample be reduced to nothing?

You have 12 kg of a radioactive substance. Ten years later, you find that you only have 3 kg left. Find the half-life of the material.

1) 1) 20 years20 years

2) 2) 10 years10 years

3) 3) 7.5 years7.5 years

4) 4) 5 years 5 years

5) 5) 2.5 years2.5 years

ConcepTest 32.10b ConcepTest 32.10b Radioactive Decay Law IIRadioactive Decay Law II

After one half-life 6 kg left. After two half-lives 3 kg left. So if the total time is 10 yearstotal time is 10 years, then the half-life must be 5 yearshalf-life must be 5 years. (2 half-lives = 10 years)

You have 12 kg of a radioactive substance. Ten years later, you find that you only have 3 kg left. Find the half-life of the material.

1) 1) 20 years20 years

2) 2) 10 years10 years

3) 3) 7.5 years7.5 years

4) 4) 5 years 5 years

5) 5) 2.5 years2.5 years

ConcepTest 32.10b ConcepTest 32.10b Radioactive Decay Law IIRadioactive Decay Law II

Follow-up:Follow-up: How much of the sample is left after another 10 years? How much of the sample is left after another 10 years?

You have 400 g of a radioactive sample with a half-life of 20 years. How much is left after 50 years?

1) more than 100 g1) more than 100 g

2) 75 - 100 g2) 75 - 100 g

3) 75 g3) 75 g

4) 50 - 75 g4) 50 - 75 g

5) less than 50 g5) less than 50 g

ConcepTest 32.10c ConcepTest 32.10c Radioactive Decay Law IIIRadioactive Decay Law III

You have 400 g of a radioactive sample with a half-life of 20 years. How much is left after 50 years?

Total time (50 years) is 2Total time (50 years) is 2 1/2 1/2 half-lives. half-lives. After one half-life 200 g left After two half-lives 100 g left. After three half-lives 50 g left. So after 2So after 2 1/2 1/2 half-lives half-lives 75 g left ? 75 g left ?

No!!No!! Exponential function is not linear!

70.7 g 70.7 g leftleft NN = = NNooee–(0.693 / –(0.693 / TT1/21/2))tt

1) more than 100 g1) more than 100 g

2) 75 - 100 g2) 75 - 100 g

3) 75 g3) 75 g

4) 50 - 75 g4) 50 - 75 g

5) less than 50 g5) less than 50 g

ConcepTest 32.10c ConcepTest 32.10c Radioactive Decay Law IIIRadioactive Decay Law III

You have two samples, A (T1/2 = 10 yr) and B

(T1/2 = 20 yr), with initially different amounts. The initial amount of sample A is 64 kg, while the amount of sample B is unknown. If you observe that the 2 amounts are equal after 40 years, what is the initial amount of B?

1) 64 kg1) 64 kg

2) 32 kg2) 32 kg

3) 16 kg3) 16 kg

4) 8 kg4) 8 kg

5) 4 kg5) 4 kg

ConcepTest 32.10d ConcepTest 32.10d Radioactive Decay Law IVRadioactive Decay Law IV

For sample A, after 40 years (4 half-lives4 half-lives) there are 4 kg4 kg left. Now work backward from there, for sample B: 40 years is 2 half-lives2 half-lives, so sample B initially had 16 kg16 kg.

You have two samples, A (T1/2 = 10 yr) and B

(T1/2 = 20 yr), with initially different amounts. The initial amount of sample A is 64 kg, while the amount of sample B is unknown. If you observe that the 2 amounts are equal after 40 years, what is the initial amount of B?

1) 64 kg1) 64 kg

2) 32 kg2) 32 kg

3) 16 kg3) 16 kg

4) 8 kg4) 8 kg

5) 4 kg5) 4 kg

ConcepTest 32.10d ConcepTest 32.10d Radioactive Decay Law IVRadioactive Decay Law IV

Follow-up:Follow-up: When will the samples again have equal amounts? When will the samples again have equal amounts?

You have 10 kg each of a radioactive sample A with a half-life of 100 years, and another sample B with a half-life of 1000 years. Which sample has the higher activity?

1) sample A1) sample A

2) sample B2) sample B

3) both the same3) both the same

4) impossible to tell 4) impossible to tell

ConcepTest 32.11a ConcepTest 32.11a Activity and Half-Life IActivity and Half-Life I

If a sample has a shorter half-lifeshorter half-life, this means that it decays more quicklydecays more quickly (larger decay constant ) and therefore has a higher activityhigher activity:

In this case, that is sample A.that is sample A.

You have 10 kg each of a radioactive sample A with a half-life of 100 years, and another sample B with a half-life of 1000 years. Which sample has the higher activity?

1) sample A1) sample A

2) sample B2) sample B

3) both the same3) both the same

4) impossible to tell 4) impossible to tell

ConcepTest 32.11a ConcepTest 32.11a Activity and Half-Life IActivity and Half-Life I

NN//tt = – = – NN

Follow-up:Follow-up: What is the ratio of activities for the two samples? What is the ratio of activities for the two samples?

The The same amountsame amount of two of two different radioactive samples different radioactive samples AA and and BB is prepared. If the is prepared. If the initial activity of initial activity of sample Asample A is is 5 5 timestimes largerlarger than that of than that of sample Bsample B, how do their half-, how do their half-lives compare?lives compare?

1) 1) TT1/21/2 of A is 5 times larger than B of A is 5 times larger than B

2) half-lives are the same2) half-lives are the same

3) 3) TT1/21/2 of A is 5 times smaller than B of A is 5 times smaller than B

ConcepTest 32.11b ConcepTest 32.11b Activity and Half-Life IIActivity and Half-Life II

A larger activitylarger activity means that a sample decays more decays more quicklyquickly, and this implies a shorter half-lifeshorter half-life.

The The same amountsame amount of two of two different radioactive samples different radioactive samples AA and and BB is prepared. If the is prepared. If the initial activity of initial activity of sample Asample A is is 5 5 timestimes largerlarger than that of than that of sample Bsample B, how do their half-, how do their half-lives compare?lives compare?

1) 1) TT1/21/2 of A is 5 times larger than B of A is 5 times larger than B

2) half-lives are the same2) half-lives are the same

3) 3) TT1/21/2 of A is 5 times smaller than B of A is 5 times smaller than B

ConcepTest 32.11b ConcepTest 32.11b Activity and Half-Life IIActivity and Half-Life II

How does the total mass of the fission fragments compare to the mass of the original nucleus in a fission reaction?

1) fission fragments have more mass 1) fission fragments have more mass

2) fission fragments have less mass 2) fission fragments have less mass

3) fission fragments have the same mass 3) fission fragments have the same mass

ConcepTest 32.12 ConcepTest 32.12 Nuclear FissionNuclear Fission

The fission reaction releases energyfission reaction releases energy, so the total energy (or mass) of the fission fragments must be lessmust be less than the energy (or mass) of the original nucleus.

How does the total mass of the fission fragments compare to the mass of the original nucleus in a fission reaction?

1) fission fragments have more mass 1) fission fragments have more mass

2) fission fragments have less mass 2) fission fragments have less mass

3) fission fragments have the same mass 3) fission fragments have the same mass

ConcepTest 32.12 ConcepTest 32.12 Nuclear FissionNuclear Fission

Follow-up:Follow-up: Where are the fission fragments Where are the fission fragments located relative to the original nucleus on located relative to the original nucleus on the curve of binding energy per nucleon?the curve of binding energy per nucleon?

How does the binding energy per nucleon of a fusion product compare to that of the pieces that combined to form it?

1) product has greater BE than the pieces 1) product has greater BE than the pieces

2) product has less BE than the pieces 2) product has less BE than the pieces

3) product has the same BE as the pieces 3) product has the same BE as the pieces

ConcepTest 32.13 ConcepTest 32.13 Nuclear FusionNuclear Fusion

The fusion reaction releases energyfusion reaction releases energy, so the product is more tightly boundproduct is more tightly bound (more stable) than the separate pieces that combined to form it. This means that the binding energy binding energy per nucleon is greater for the fusion per nucleon is greater for the fusion productproduct.

How does the binding energy per nucleon of a fusion product compare to that of the pieces that combined to form it?

1) product has greater BE than the pieces 1) product has greater BE than the pieces

2) product has less BE than the pieces 2) product has less BE than the pieces

3) product has the same BE as the pieces 3) product has the same BE as the pieces

ConcepTest 32.13 ConcepTest 32.13 Nuclear FusionNuclear Fusion

Follow-up:Follow-up: Which weighs more: Which weighs more: the fusion product or the pieces?the fusion product or the pieces?

Which type of radiation goes farther in matter before losing all of its energy ?

1) alpha radiation

2) beta radiation

3) gamma radiation

4) all about the same distance

ConcepTest 32.14 ConcepTest 32.14 Radiation ShieldingRadiation Shielding

paper aluminum lead

Alpha particles have such a large charge that they ionize many atoms in a short distance, and so lose their energy rapidly and stop. Gamma rays travel great distances before ionizing an atom.

Which type of radiation goes farther in matter before losing all of its energy ?

1) alpha radiation

2) beta radiation

3) gamma radiation

4) all about the same distance

ConcepTest 32.14 ConcepTest 32.14 Radiation ShieldingRadiation Shielding

Curly is twice as far from a small radioactive source as Moe. Compared to Curly’s position, the intensity of the radiation (and therefore exposure) at Moe’s position is about:

1) one-quarter2) one-half3) the same4) double5) quadruple

CurlyMoeradioactive source

ConcepTest 32.15a ConcepTest 32.15a Radiation Exposure IRadiation Exposure I

A small source can be treated as a point source and so it obeys the inverse square lawobeys the inverse square law of intensity. Twice as close Twice as close means 4 times the intensitymeans 4 times the intensity (and therefore exposure).

Curly is twice as far from a small radioactive source as Moe. Compared to Curly’s position, the intensity of the radiation (and therefore exposure) at Moe’s position is about:

1) one-quarter2) one-half3) the same4) double5) quadruple

CurlyMoeradioactive source

ConcepTest 32.15a ConcepTest 32.15a Radiation Exposure IRadiation Exposure I

Curly is working 5 m from a highly radioactive source and must reduce his exposure by at least a factor of 10. Assuming that an inverse square law (1/r2) applies in this case, to what distance should he move?

1) 7.5 m

2) 10 m

3) 15 m

4) 20 m

5) 50 m

Curlyradioactive source

ConcepTest 32.15b ConcepTest 32.15b Radiation Exposure IIRadiation Exposure II

A small source can be treated like a point source and so it obeys the inverse square lawobeys the inverse square law of intensity. Moving to 15 m15 m (3 times farther) only reduces the exposure by 9 timesreduces the exposure by 9 times. He has to move farther away (20 m20 m) in order to get a factor of factor of 16 reduction16 reduction, which meets the “safety limit” of 10 times.

Curly is working 5 m from a highly radioactive source and must reduce his exposure by at least a factor of 10. Assuming that an inverse square law (1/r2) applies in this case, to what distance should he move?

1) 7.5 m

2) 10 m

3) 15 m

4) 20 m

5) 50 m

Curlyradioactive source

ConcepTest 32.15b ConcepTest 32.15b Radiation Exposure IIRadiation Exposure II

Radiation can damage matter such as metals or biological tissue by:

1) heating up the material

2) causing cancer in the metal

3) producing fission reactions in the material

4) removing electrons from the atoms

5) producing fusion reactions in the material

ConcepTest 32.16 ConcepTest 32.16 Radiation DamageRadiation Damage

Radiation can ionize the atoms in matter, which means knocking out electrons. Metals become brittle and cell processes can be disrupted.

Radiation can damage matter such as metals or biological tissue by:

1) heating up the material

2) causing cancer in the metal

3) producing fission reactions in the material

4) removing electrons from the atoms

5) producing fusion reactions in the material

ConcepTest 32.16 ConcepTest 32.16 Radiation DamageRadiation Damage

Follow-up:Follow-up: What type of radiation will tend to do the most damage? What type of radiation will tend to do the most damage?