23. Nuclear physics

understand the equivalence between energy and mass as represented by E = mc 2 and recall and use this equation.

Use —the equivalence between energy and mass as represented by e = mc 2 and to connect the rule to the data and decision in the question.

This matters because —the equivalence between energy and mass as represented by e = mc 2 and determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the equivalence between energy and mass as represented by e = mc 2 and to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The equivalence between energy and mass as represented by E = mc 2 and is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

represent simple nuclear reactions by nuclear equations of the form NH eO H7 14 2 4 8 17 1 1"++.

Use —simple nuclear reactions by nuclear equations of the form nh eo h7 14 2 4 8 to connect the rule to the data and decision in the question.

This matters because —simple nuclear reactions by nuclear equations of the form nh eo h7 14 2 4 8 determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —simple nuclear reactions by nuclear equations of the form nh eo h7 14 2 4 8 to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: use the formula and units given in the question, show the substitution and interpret the result; the calculation alone is not the conclusion.

define and use the terms mass defect and binding energy.

Use —the terms mass defect and binding energy to connect the rule to the data and decision in the question.

This matters because —the terms mass defect and binding energy determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the terms mass defect and binding energy to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The terms mass defect and binding energy is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

sketch the variation of binding energy per nucleon with nucleon number.

Use —the variation of binding energy per nucleon with nucleon number to connect the rule to the data and decision in the question.

This matters because —the variation of binding energy per nucleon with nucleon number determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the variation of binding energy per nucleon with nucleon number to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The variation of binding energy per nucleon with nucleon number is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

explain what is meant by nuclear fusion and nuclear fission.

Use —what is meant by nuclear fusion and nuclear fission to connect the rule to the data and decision in the question.

This matters because —what is meant by nuclear fusion and nuclear fission determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —what is meant by nuclear fusion and nuclear fission to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —What is meant by nuclear fusion and nuclear fission is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

explain the relevance of binding energy per nucleon to nuclear reactions, including nuclear fusion and nuclear fission.

Use —the relevance of binding energy per nucleon to nuclear reactions to connect the rule to the data and decision in the question.

This matters because —the relevance of binding energy per nucleon to nuclear reactions determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the relevance of binding energy per nucleon to nuclear reactions to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The relevance of binding energy per nucleon to nuclear reactions is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

calculate the energy released in nuclear reactions using E = c 2∆m.

Use —the energy released in nuclear reactions using e = c 2∆m to connect the rule to the data and decision in the question.

This matters because —the energy released in nuclear reactions using e = c 2∆m determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the energy released in nuclear reactions using e = c 2∆m to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The energy released in nuclear reactions using E = c 2∆m is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

understand that fluctuations in count rate provide evidence for the random nature of radioactive decay.

Use —fluctuations in count rate provide evidence for the random nature of to connect the rule to the data and decision in the question.

This matters because —fluctuations in count rate provide evidence for the random nature of determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —fluctuations in count rate provide evidence for the random nature of to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Fluctuations in count rate provide evidence for the random nature of is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

understand that radioactive decay is both spontaneous and random.

Use —radioactive decay is both spontaneous and random to connect the rule to the data and decision in the question.

This matters because —radioactive decay is both spontaneous and random determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —radioactive decay is both spontaneous and random to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Radioactive decay is both spontaneous and random is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

define activity and decay constant, and recall and use A = λN.

Use —activity and decay constant, and recall and use a = λn to connect the rule to the data and decision in the question.

This matters because —activity and decay constant, and recall and use a = λn determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —activity and decay constant, and recall and use a = λn to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Activity and decay constant, and recall and use A = λN is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

define half-life.

Use —half-life to connect the rule to the data and decision in the question.

This matters because —half-life determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —half-life to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Half-life is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

use λ = 0.693 / t 1/2.

Use —λ = 0.693 / t 1/2 to connect the rule to the data and decision in the question.

This matters because —λ = 0.693 / t 1/2 determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —λ = 0.693 / t 1/2 to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Λ = 0.693 / t 1/2 is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

understand the exponential nature of radioactive decay, and sketch and use the relationship x = x 0e–λt, where x could represent activity, number of undecayed nuclei or received count rate.

Use —the exponential nature of radioactive decay, and sketch and use the to connect the rule to the data and decision in the question.

This matters because —the exponential nature of radioactive decay, and sketch and use the determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the exponential nature of radioactive decay, and sketch and use the to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The exponential nature of radioactive decay, and sketch and use the is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.