A patient receives A rad of radiation as part of her treatment and absorbs E J of energy. The RBE of the radiation particles is R. If the RBE is increased to 1.5R, what will be the energy absorbed by the patient?

1. 1.5E J
2. E J
3. 0.75E J
4. 0.67E J

If a 90-kg person is exposed to 50 mrem of alpha particles (with RBE of 16), calculate the dosage (in rad) received by the person. What is the amount of energy absorbed by the person?

Figure 15.31

This figure shows a graph of the potential energy between two light nuclei as a function of the distance between them. Fusion can occur between the nuclei if the distance is

1. large so that kinetic energy is low.
2. large so that potential energy is low.
3. small so that nuclear attractive force can overcome Coulomb’s repulsion.
4. small so that nuclear attractive force cannot overcome Coulomb’s repulsion.

In a nuclear fusion reaction, 2 g of hydrogen is converted into 1.985 g of helium. What is the energy released?

1. 4.5 × 10³ J
2. 4.5 × 10⁶ J
3. 1.35 × 10¹² J
4. 1.35 × 10¹⁵ J

When deuterium and tritium nuclei fuse to produce helium, what else is produced?

1. Positron
2. Proton
3. α-particle
4. Neutron

Suppose two deuterium nuclei are fused to produce helium.

1. Write the equation for the fusion reaction.
2. Calculate the difference between the masses of reactants and products.
3. Using the result calculated in (b), find the energy produced in the fusion reaction.

Assume that the mass of deuterium is 2.014102 u, the mass of helium is 4.002603 u and 1 u = 1.66 × 10^–27 kg.

Which of the following statements about nuclear fission is true?

1. No new elements can be produced in a fission reaction.
2. Energy released in fission reactions is generally less than that from fusion reactions.
3. In a fission reaction, two light nuclei are combined into a heavier one.
4. Fission reactions can be explained on the basis of the conservation of mass-energy.

What is the energy obtained when 10 g of mass is converted to energy with an efficiency of 70 percent?

1. 3.93 × 10²⁷ MeV
2. 3.93 × 10³⁰ MeV
3. 5.23 × 10²⁷ MeV
4. 5.23 × 10³⁰ MeV

In a neutron-induced fission reaction of ²³⁹Pu, which of the following is produced along with ⁹⁶Sr and four neutrons?

1. ${}_{56}^{139}\text{Ba}$
2. ${}_{56}^{140}\text{Ba}$
3. ${}_{54}^{139}\text{Xe}$
4. ${}_{54}^{140}\text{Xe}$

When ²³⁵U is bombarded with one neutron, the following fission reaction occurs: ${}_{92}^{235}\text{U}\text{+}n\to {}_{56}^{141}\text{Ba}\text{+}{}_y^{92}\text{Kr}\text{+}xn\text{.}$

1. Find the values for x and y.
2. Assuming that the mass of ²³⁵U is 235.04 u, the mass of ¹⁴¹Ba is 140.91 u, the mass of ⁹²Kr is 91.93 u, and the mass of n is 1.01 u, a student calculates the energy released in the fission reaction as 2.689 × 10⁻⁸, but forgets to write the unit. Find the correct unit and convert the answer to MeV.