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Nuclear

Environmental Engineering · FE Reference Handbook section

Environmental Engineering
0 formulas
10 exam-style examples
~45 min
All Environmental Engineering lectures

Handbook notes for this section

Definitions and conditions exactly as the handbook states them.

  • Nuclear Power Reactor Characteristics
  • Typical Reactor Pressure, Typical Fuel
  • Reactor Thermal Density, Heat Flux, Reactor

Core formulas for this FE topic

Definitions, applicability, units, assumptions and worked examples for each relation.

This section is conceptual; there are no equations to memorise.

Worked exam-style examples

The four ways this section is written on the real exam — thoughts first, then equations, then substitution.

Example 1
Nuclear — solve for energy released — Nuclear

nuclear energy released from a fission mass defect calculation Given mass defect (dm) = 0.0006 kg; speed of light (c) = 300,000,000 m/s, determine the energy released (E) in J.

Given

  • massdefect(dm)=0.0006kgmass defect (dm) = 0.0006 kg
  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s

Find

energy released (E), in J

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for E:

    E=Δm c2E = \Delta m\,c^2
  3. Step 3

    Listthegivens:massdefect(dm)=0.0006kg,speedoflight(c)=300,000,000m/sList the givens: mass defect (dm) = 0.0006 kg, speed of light (c) = 300,000,000 m/s
  4. Step 4 — Substitute the given values:

    E=Δm 3000000002E = \Delta m\,300000000^2
  5. Step 5 — Evaluate:

    E=51840000000000 JE = 51840000000000\ \text{J}
  6. Step 6 — Check: returning E = 51,840,000,000,000 J to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=51840000000000 JE = 51840000000000\ \text{J}

Why the other options are there

  • 103,680,000,000,000 — kept a factor of two that cancels in the correct rearrangement.
  • 25,920,000,000,000 — dropped that same factor in the other direction.
  • 57,024,000,000,000 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 2
Nuclear — solve for mass defect — Nuclear (2)

nuclear power plant energy output from mass-energy equivalence Given speed of light (c) = 300,000,000 m/s; energy released (E) = 34,778,000,000,000 J, determine the mass defect (dm) in kg.

Given

  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s
  • energyreleased(E)=34,778,000,000,000Jenergy released (E) = 34,778,000,000,000 J

Find

mass defect (dm), in kg

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except dm is given, so isolate dm symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for dm:

    dm=Ec2dm = \dfrac{E}{c^2}
  3. Step 3

    Listthegivens:speedoflight(c)=300,000,000m/s,energyreleased(E)=34,778,000,000,000JList the givens: speed of light (c) = 300,000,000 m/s, energy released (E) = 34,778,000,000,000 J
  4. Step 4 — Substitute the given values:

    dm=347780000000003000000002dm = \dfrac{34778000000000}{300000000^2}
  5. Step 5 — Evaluate:

    dm=0.0004 kgdm = 0.0004\ \text{kg}
  6. Step 6 — Check: returning dm = 0.0004 kg to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
dm=0.0004 kgdm = 0.0004\ \text{kg}

Why the other options are there

  • 0.0008 — kept a factor of two that cancels in the correct rearrangement.
  • 0.0002 — dropped that same factor in the other direction.
  • 0.0004 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 3
Nuclear — solve for energy released (case 2) — Nuclear (3)

nuclear reaction energy release estimated from mass defect Given mass defect (dm) = 0.0002 kg; speed of light (c) = 300,000,000 m/s, determine the energy released (E) in J.

Given

  • massdefect(dm)=0.0002kgmass defect (dm) = 0.0002 kg
  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s

Find

energy released (E), in J

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for E:

    E=Δm c2E = \Delta m\,c^2
  3. Step 3

    Listthegivens:massdefect(dm)=0.0002kg,speedoflight(c)=300,000,000m/sList the givens: mass defect (dm) = 0.0002 kg, speed of light (c) = 300,000,000 m/s
  4. Step 4 — Substitute the given values:

    E=Δm 3000000002E = \Delta m\,300000000^2
  5. Step 5 — Evaluate:

    E=15570000000000 JE = 15570000000000\ \text{J}
  6. Step 6 — Check: returning E = 15,570,000,000,000 J to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=15570000000000 JE = 15570000000000\ \text{J}

Why the other options are there

  • 31,140,000,000,000 — kept a factor of two that cancels in the correct rearrangement.
  • 7,785,000,000,000 — dropped that same factor in the other direction.
  • 17,127,000,000,000 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 4
Nuclear — solve for mass defect (case 2) — Nuclear (4)

nuclear energy released from a fission mass defect calculation Given speed of light (c) = 300,000,000 m/s; energy released (E) = 39,640,000,000,000 J, determine the mass defect (dm) in kg.

Given

  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s
  • energyreleased(E)=39,640,000,000,000Jenergy released (E) = 39,640,000,000,000 J

Find

mass defect (dm), in kg

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except dm is given, so isolate dm symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for dm:

    dm=Ec2dm = \dfrac{E}{c^2}
  3. Step 3

    Listthegivens:speedoflight(c)=300,000,000m/s,energyreleased(E)=39,640,000,000,000JList the givens: speed of light (c) = 300,000,000 m/s, energy released (E) = 39,640,000,000,000 J
  4. Step 4 — Substitute the given values:

    dm=396400000000003000000002dm = \dfrac{39640000000000}{300000000^2}
  5. Step 5 — Evaluate:

    dm=0.0004 kgdm = 0.0004\ \text{kg}
  6. Step 6 — Check: returning dm = 0.0004 kg to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
dm=0.0004 kgdm = 0.0004\ \text{kg}

Why the other options are there

  • 0.0009 — kept a factor of two that cancels in the correct rearrangement.
  • 0.0002 — dropped that same factor in the other direction.
  • 0.0005 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 5
Nuclear — solve for energy released (case 3) — Nuclear (5)

nuclear power plant energy output from mass-energy equivalence Given mass defect (dm) = 0.0007 kg; speed of light (c) = 300,000,000 m/s, determine the energy released (E) in J.

Given

  • massdefect(dm)=0.0007kgmass defect (dm) = 0.0007 kg
  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s

Find

energy released (E), in J

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for E:

    E=Δm c2E = \Delta m\,c^2
  3. Step 3

    Listthegivens:massdefect(dm)=0.0007kg,speedoflight(c)=300,000,000m/sList the givens: mass defect (dm) = 0.0007 kg, speed of light (c) = 300,000,000 m/s
  4. Step 4 — Substitute the given values:

    E=Δm 3000000002E = \Delta m\,300000000^2
  5. Step 5 — Evaluate:

    E=63270000000000 JE = 63270000000000\ \text{J}
  6. Step 6 — Check: returning E = 63,270,000,000,000 J to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=63270000000000 JE = 63270000000000\ \text{J}

Why the other options are there

  • 126,540,000,000,000 — kept a factor of two that cancels in the correct rearrangement.
  • 31,635,000,000,000 — dropped that same factor in the other direction.
  • 69,597,000,000,000 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 6
Nuclear — solve for mass defect (case 3) — Nuclear (6)

nuclear reaction energy release estimated from mass defect Given speed of light (c) = 300,000,000 m/s; energy released (E) = 62,457,000,000,000 J, determine the mass defect (dm) in kg.

Given

  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s
  • energyreleased(E)=62,457,000,000,000Jenergy released (E) = 62,457,000,000,000 J

Find

mass defect (dm), in kg

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except dm is given, so isolate dm symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for dm:

    dm=Ec2dm = \dfrac{E}{c^2}
  3. Step 3

    Listthegivens:speedoflight(c)=300,000,000m/s,energyreleased(E)=62,457,000,000,000JList the givens: speed of light (c) = 300,000,000 m/s, energy released (E) = 62,457,000,000,000 J
  4. Step 4 — Substitute the given values:

    dm=624570000000003000000002dm = \dfrac{62457000000000}{300000000^2}
  5. Step 5 — Evaluate:

    dm=0.0007 kgdm = 0.0007\ \text{kg}
  6. Step 6 — Check: returning dm = 0.0007 kg to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
dm=0.0007 kgdm = 0.0007\ \text{kg}

Why the other options are there

  • 0.0014 — kept a factor of two that cancels in the correct rearrangement.
  • 0.0003 — dropped that same factor in the other direction.
  • 0.0008 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 7
Nuclear — solve for energy released (case 4) — Nuclear (7)

nuclear energy released from a fission mass defect calculation Given mass defect (dm) = 0.0010 kg; speed of light (c) = 300,000,000 m/s, determine the energy released (E) in J.

Given

  • massdefect(dm)=0.0010kgmass defect (dm) = 0.0010 kg
  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s

Find

energy released (E), in J

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for E:

    E=Δm c2E = \Delta m\,c^2
  3. Step 3

    Listthegivens:massdefect(dm)=0.0010kg,speedoflight(c)=300,000,000m/sList the givens: mass defect (dm) = 0.0010 kg, speed of light (c) = 300,000,000 m/s
  4. Step 4 — Substitute the given values:

    E=Δm 3000000002E = \Delta m\,300000000^2
  5. Step 5 — Evaluate:

    E=89820000000000 JE = 89820000000000\ \text{J}
  6. Step 6 — Check: returning E = 89,820,000,000,000 J to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=89820000000000 JE = 89820000000000\ \text{J}

Why the other options are there

  • 179,640,000,000,000 — kept a factor of two that cancels in the correct rearrangement.
  • 44,910,000,000,000 — dropped that same factor in the other direction.
  • 98,802,000,000,000 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 8
Nuclear — solve for mass defect (case 4) — Nuclear (8)

nuclear power plant energy output from mass-energy equivalence Given speed of light (c) = 300,000,000 m/s; energy released (E) = 23,801,000,000,000 J, determine the mass defect (dm) in kg.

Given

  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s
  • energyreleased(E)=23,801,000,000,000Jenergy released (E) = 23,801,000,000,000 J

Find

mass defect (dm), in kg

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except dm is given, so isolate dm symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for dm:

    dm=Ec2dm = \dfrac{E}{c^2}
  3. Step 3

    Listthegivens:speedoflight(c)=300,000,000m/s,energyreleased(E)=23,801,000,000,000JList the givens: speed of light (c) = 300,000,000 m/s, energy released (E) = 23,801,000,000,000 J
  4. Step 4 — Substitute the given values:

    dm=238010000000003000000002dm = \dfrac{23801000000000}{300000000^2}
  5. Step 5 — Evaluate:

    dm=0.0003 kgdm = 0.0003\ \text{kg}
  6. Step 6 — Check: returning dm = 0.0003 kg to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
dm=0.0003 kgdm = 0.0003\ \text{kg}

Why the other options are there

  • 0.0005 — kept a factor of two that cancels in the correct rearrangement.
  • 0.0001 — dropped that same factor in the other direction.
  • 0.0003 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 9
Nuclear — solve for energy released (case 5) — Nuclear (9)

nuclear reaction energy release estimated from mass defect Given mass defect (dm) = 0.0007 kg; speed of light (c) = 300,000,000 m/s, determine the energy released (E) in J.

Given

  • massdefect(dm)=0.0007kgmass defect (dm) = 0.0007 kg
  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s

Find

energy released (E), in J

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except E is given, so isolate E symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for E:

    E=Δm c2E = \Delta m\,c^2
  3. Step 3

    Listthegivens:massdefect(dm)=0.0007kg,speedoflight(c)=300,000,000m/sList the givens: mass defect (dm) = 0.0007 kg, speed of light (c) = 300,000,000 m/s
  4. Step 4 — Substitute the given values:

    E=Δm 3000000002E = \Delta m\,300000000^2
  5. Step 5 — Evaluate:

    E=63900000000000 JE = 63900000000000\ \text{J}
  6. Step 6 — Check: returning E = 63,900,000,000,000 J to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
E=63900000000000 JE = 63900000000000\ \text{J}

Why the other options are there

  • 127,800,000,000,000 — kept a factor of two that cancels in the correct rearrangement.
  • 31,950,000,000,000 — dropped that same factor in the other direction.
  • 70,290,000,000,000 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

Example 10
Nuclear — solve for mass defect (case 5) — Nuclear (10)

nuclear energy released from a fission mass defect calculation Given speed of light (c) = 300,000,000 m/s; energy released (E) = 4,983,000,000,000 J, determine the mass defect (dm) in kg.

Given

  • speedoflight(c)=300,000,000m/sspeed of light (c) = 300,000,000 m/s
  • energyreleased(E)=4,983,000,000,000Jenergy released (E) = 4,983,000,000,000 J

Find

mass defect (dm), in kg

Start with the thinking

  • The governing relation printed in this handbook section is Nuclear.
  • Everything except dm is given, so isolate dm symbolically first — never rearrange after the numbers are in.
  • Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
  • Nuclear energy release in a reactor is described by mass-energy equivalence between mass defect and energy produced.

Step-by-step solution

  1. Step 1 — State the governing relation:

    E=Δm c2E = \Delta m \, c^2
  2. Step 2 — Rearrange symbolically for dm:

    dm=Ec2dm = \dfrac{E}{c^2}
  3. Step 3

    Listthegivens:speedoflight(c)=300,000,000m/s,energyreleased(E)=4,983,000,000,000JList the givens: speed of light (c) = 300,000,000 m/s, energy released (E) = 4,983,000,000,000 J
  4. Step 4 — Substitute the given values:

    dm=49830000000003000000002dm = \dfrac{4983000000000}{300000000^2}
  5. Step 5 — Evaluate:

    dm=0.0001 kgdm = 0.0001\ \text{kg}
  6. Step 6 — Check: returning dm = 0.0001 kg to

    E=Δm c2E = \Delta m \, c^2

    reproduces the given quantities, and both sides carry the same units.

Answer:
dm=0.0001 kgdm = 0.0001\ \text{kg}

Why the other options are there

  • 0.0001 — kept a factor of two that cancels in the correct rearrangement.
  • 0.0000 — dropped that same factor in the other direction.
  • 0.0001 — rounded an intermediate value before the final step.

Reference: FE Handbook — Nuclear Energy

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