Connected Rates of Change (Edexcel A-Level Mathematics): Flashcards

Changes in one variable affect changes in another variable.

Identify the quantities that change with respect to time.

To differentiate equations related to changing quantities.

$A = \pi r^2$, where $r$ is the radius of the circle.

$dA/dt = 2\pi r(dr/dt)$, using implicit differentiation.

Volume $V = (1/3)\pi r^2 h$, with $r$ in terms of $h$.

Indicates volume is decreasing over time.

$dA/dt = 20\pi$ cm²/s using $A=\pi r^2$ formula.

Ensure the solution is contextually sensible.

Geometry, motion problems, fluid dynamics, and engineering.