Question 1

Consider the fission reaction:  +  → 2 fission products + 2 n's
(a) Estimate the energy released in the reaction.
(b) If 3 neutrons had been released instead of 2, what energy would have been released?

Accepted Answer

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Question 2

What is the missing term in this fission reaction:  +  →  + ? + 4

Accepted Answer

The answer of What is the missing term in this...

Question 3

In the fission reaction ²³⁵U + ¹n $\rightarrow$ ¹⁴¹Ba + ⁹²Kr + neutrons, the number of neutrons produced is

Accepted Answer

In the fission of Uranium-235 by a neutron, typically three neutrons are produced along with the fission fragments Barium-141 and Krypton-92.

Question 4

The threshold energy to initiate a certain nuclear reaction is 3.16 MeV and the Q for the reaction is -2.37 MeV. The stationary target is how many times as massive as the incident particle?

Accepted Answer

The answer of The threshold energy to initiate a certain...

Question 5

What is the Q-value of the following reaction? ¹⁴N + ⁴He = ¹p + ¹⁷O (14.003074) (4.002603) (1.007825) (16.999131)

Accepted Answer

The answer of What is the Q-value of the following...

Question 6

What is the Q value for the following reaction? ⁷Li +¹p = ⁴He + ⁴He (7.016005) (1.007825) (4.002603) (4.002603)

Accepted Answer

The Q value is calculated using the mass-energy equivalence principle. The mass defect is the difference between the initial and final masses, converted to energy using E=mc². The initial mass is 7.016005 + 1.007825 = 8.02383 u, and the final mass is 2 * 4.002603 = 8.005206 u. The mass defect is 8.02383 - 8.005206 = 0.018624 u. Converting this to energy (1 u = 931.5 MeV), the Q value is 0.018624 * 931.5 = 17.35 MeV.

Question 7

When a neutron collides with a uranium-235 nucleus it can induce a variety of fission reactions. One such reaction is + $\rightarrow$ + + 2 . Given the following mass values: , 139.921620 u; , 93.915367 u; , 235.043924 u; , 1.008665 u, how much energy is released in this reaction? 1 u = 931.494 MeV/c².

Accepted Answer

The answer of When a neutron collides with a uranium-235...

Question 8

If a reactor produces an average power of 1000 MW for a year, how much mass is turned into energy?

Accepted Answer

The answer of If a reactor produces an average power...

Question 9

If a 2.0-MeV neutron released in a fission reaction loses half its energy in each moderator collision, how many collisions are needed to bring it to (1/25) eV?

Accepted Answer

The energy of the neutron is halved with each collision. Starting from 2.0 MeV, the energy after n collisions is (2.0 MeV) * (1/2)^n. To find n when the energy is (1/25) eV, convert 2.0 MeV to eV (2.0 MeV = 2.0 x 10^6 eV) and solve (2.0 x 10^6) * (1/2)^n = 1/25. Solving for n gives approximately 26 collisions.

Question 10

Determine the missing reaction product: ¹n + ²³⁵U = ¹⁴¹Ba + ________ + 3(¹n )

Accepted Answer

The answer of Determine the missing reaction product: ¹n +...

Question 11

Find the Q value of the following reaction:  +  →  +  (14.003074 u) (4.002603 u) (16.999131 u) (1.007825 u)

Accepted Answer

The answer of Find the Q value of the following...

Question 12

Complete the following reaction: ¹n + ¹⁰B → ⁴He + ________

Accepted Answer

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Question 13

A beam of protons is sent through a target and 60% get through. If the target then has its thickness doubled, what percent of the beam would then get through?

Accepted Answer

The transmission of protons through a material typically follows an exponential decay model. If 60% get through initially, doubling the thickness would square the transmission probability, resulting in 0.6 * 0.6 = 0.36 or 36%.

Question 14

The Q value for a particular reaction is -2.4 MeV, and the reaction's threshold energy is 9.60 MeV. What is the ratio of the mass of the incident particle to the mass of the stationary target nucleus?

Accepted Answer

The threshold energy (Eth) is related to the Q value and the masses of the particles involved. For a reaction with a negative Q value, Eth = -Q * (1 + m1/m2), where m1 is the mass of the incident particle and m2 is the mass of the target nucleus. Solving for m1/m2 gives m1/m2 = Eth/(-Q) - 1 = 9.60/2.4 - 1 = 3.

Question 15

A beam of 10¹² neutrons/second is incident on an aluminum foil of thickness 10^-4 m. The cross section for absorption is 0.23 bn. What is the reaction rate for neutrons being absorbed?

Accepted Answer

The answer of A beam of 10¹² neutrons/second is incident...

Question 16

A proton strikes an Oxygen-18 nucleus producing Fluorine-18 and another particle. What other particle is produced by this nuclear reaction?

Accepted Answer

A proton has a charge of +1 and an atomic number of 1. Oxygen-18 has a charge of +8 and an atomic number of 8. Fluorine-18 has a charge of +9 and an atomic number of 9. Therefore, the other particle produced by this nuclear reaction must have a charge of -1 and an atomic number of 0. This particle is a neutron.

Question 17

Complete the following nuclear reaction:  +  → ________ +

Accepted Answer

The answer of Complete the following nuclear reaction:  +...

Question 18

The thermal neutron cross section of a proton is 0.33 bn. If this cross-section were to represent the circular cross-sectional area of the proton presented to the neutron beam, what would be the radius of the proton?

Accepted Answer

The answer of The thermal neutron cross section of a...

Question 19

In the fissioning of uranium, the typical amount of energy released per nucleon is

Accepted Answer

In the fissioning of uranium, the energy released per nucleon is approximately 0.9 MeV. This is because the total energy released in a typical uranium fission event is about 200 MeV, and since uranium-235 has 235 nucleons, the energy per nucleon is around 0.9 MeV.

Question 20

Find the Q value of the following reaction:  +  →  +  (14.003074 u) (4.002603) (16.999131 u) (1.007825 u)

Accepted Answer

The answer of Find the Q value of the following...

Quiz 42: Nuclear Energy: Efects and Uses of Radiation

Consider the fission reaction: + → 2 fission products + 2 n's (a) Estimate the energy released in the reaction. (b) If 3 neutrons had been released instead of 2, what energy would have been released?

What is the missing term in this fission reaction: + → + ? + 4

In the fission reaction 235U + 1n →\rightarrow→ 141Ba + 92Kr + neutrons, the number of neutrons produced is

The threshold energy to initiate a certain nuclear reaction is 3.16 MeV and the Q for the reaction is -2.37 MeV. The stationary target is how many times as massive as the incident particle?

What is the Q-value of the following reaction? 14N + 4He = 1p + 17O (14.003074) (4.002603) (1.007825) (16.999131)

What is the Q value for the following reaction? 7Li + 1p = 4He + 4He (7.016005) (1.007825) (4.002603) (4.002603)

If a reactor produces an average power of 1000 MW for a year, how much mass is turned into energy?

If a 2.0-MeV neutron released in a fission reaction loses half its energy in each moderator collision, how many collisions are needed to bring it to (1/25) eV?

Determine the missing reaction product: 1n + 235U = 141Ba + ________ + 3(1n )

Find the Q value of the following reaction: + → + (14.003074 u) (4.002603 u) (16.999131 u) (1.007825 u)

Complete the following reaction: 1n + 10B → 4He + ________