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Differential Calculus2D

Applications of the Derivative - Theory & Concepts - Cone Related Rates

Apply differentiation to solve problems in motion, optimization, geometric analysis, and marginal cost.

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Hydraulic Related Rates: Conical Reservoir

A standard civil engineering application: analyze how depth hh changes over time as water flows into a conical tank at a constant rate dV/dtdV/dt.

0.1m10m (Full)
Governing Equation
dhdt=dV/dtπr2\frac{dh}{dt} = \frac{dV/dt}{\pi r^2}
Current Radius $r$:
2.00 m
Water Volume $V$:
16.8
Rate dh/dt:0.1194 m/min
Reservoir Geometry Cross-Section
R = 5mH = 10mr = 2.00mh = 4.0mQin = 1.5 m³/min
Depth vs. Depth Rate (dh/dt)
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Key Insight: Observe how the green curve decreases exponentially. As the depth hh increases, the cross-sectional area expands, meaning the rate of vertical rise dh/dtdh/dt slows down drastically for the same constant inflow!