C.3 Graphs

Translate information between graphical, numerical and algebraic forms, including using stress–strain graphs to calculate Young modulus.

Use c.3.1—translating between data forms to connect the rule to the data and decision in the question.

This matters because c.3.1—translating between data forms determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.1—translating between data forms to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.1—Translating between data forms is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Plot two variables from experimental or other data, including extension against applied force.

Use c.3.2—plotting two variables to connect the rule to the data and decision in the question.

This matters because c.3.2—plotting two variables determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.2—plotting two variables to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.2—Plotting two variables is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand that y = mx + c represents a linear relationship and compare physical equations with that form.

Use c.3.3—linear relationships to connect the rule to the data and decision in the question.

This matters because c.3.3—linear relationships determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.3—linear relationships to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.3—Linear relationships is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Determine the slope and intercept of a linear graph and interpret their physical significance.

Use c.3.4—slope and intercept to connect the rule to the data and decision in the question.

This matters because c.3.4—slope and intercept determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.4—slope and intercept to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.4—Slope and intercept is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Calculate rate of change from a graph showing a linear relationship, such as acceleration from a velocity–time graph.

Use c.3.5—rate from a linear graph to connect the rule to the data and decision in the question.

This matters because c.3.5—rate from a linear graph determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.5—rate from a linear graph to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.5—Rate from a linear graph is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Draw and use the slope of a tangent to a curve as a measure of rate of change.

Use c.3.6—tangents and instantaneous rates to connect the rule to the data and decision in the question.

This matters because c.3.6—tangents and instantaneous rates determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.6—tangents and instantaneous rates to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.6—Tangents and instantaneous rates is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Distinguish between instantaneous and average rates of change and interpret them physically.

Use c.3.7—instantaneous and average rates to connect the rule to the data and decision in the question.

This matters because c.3.7—instantaneous and average rates determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.7—instantaneous and average rates to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.7—Instantaneous and average rates is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Interpret and calculate or estimate the physical significance of the area between a curve and the x-axis. A2 applications include energy stored under a capacitor voltage–charge graph.

Use c.3.8—area under a graph to connect the rule to the data and decision in the question.

This matters because c.3.8—area under a graph determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.8—area under a graph to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.8—Area under a graph is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Apply concepts underlying calculus without explicit differentiation or integration by solving rate-of-change equations graphically or with spreadsheet modelling.

Use c.3.9—graphical calculus concepts to connect the rule to the data and decision in the question.

This matters because c.3.9—graphical calculus concepts determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.9—graphical calculus concepts to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.9—Graphical calculus concepts is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Interpret logarithmic plots, including obtaining a capacitor-discharge time constant from log voltage against time.

Use c.3.10—interpreting logarithmic plots to connect the rule to the data and decision in the question.

This matters because c.3.10—interpreting logarithmic plots determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.10—interpreting logarithmic plots to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.10—Interpreting logarithmic plots is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Use logarithmic plots to test exponential and power-law variations, including radioactive decay and capacitor charging or discharging.

Use c.3.11—testing laws with logarithmic plots to connect the rule to the data and decision in the question.

This matters because c.3.11—testing laws with logarithmic plots determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.11—testing laws with logarithmic plots to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.11—Testing laws with logarithmic plots is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Sketch relationships modelled by reciprocal, inverse-square, square, linear, trigonometric and exponential functions. Exponential and squared-trigonometric forms are A2-only applications.

Use c.3.12—sketching modelled relationships to connect the rule to the data and decision in the question.

This matters because c.3.12—sketching modelled relationships determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply c.3.12—sketching modelled relationships to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: C.3.12—Sketching modelled relationships is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.