The radius of the base of a cone is increasing at a rate of 10 meters per second.The height of the cone is fixed at 6 meters.At a certain instant, the radius is 1 meter.What is the rate of change of the volume of the cone at that instant (in cubic meters per second)?Choose 1 answer:(A) 20π(B) 40π(C) 400π(D) 200πThe volume of a cone with radius r and height h is πr23h.
Q. The radius of the base of a cone is increasing at a rate of 10 meters per second.The height of the cone is fixed at 6 meters.At a certain instant, the radius is 1 meter.What is the rate of change of the volume of the cone at that instant (in cubic meters per second)?Choose 1 answer:(A) 20π(B) 40π(C) 400π(D) 200πThe volume of a cone with radius r and height h is πr23h.
Volume Formula Derivation: The formula for the volume of a cone is V=(31)πr2h. We need to find dtdV, the rate of change of volume with respect to time.
Given Information: Given: dtdr=10m/s (rate at which radius increases), h=6m (height of the cone is constant), and r=1m (radius at the instant we are considering).
Differentiation with Respect to Time: Differentiate the volume formula with respect to time t to find dtdV. dtdV=31πdtd(r2)h.
Substitution and Calculation: Since r2 differentiates to 2r⋅dtdr, we substitute dtdr=10m/s and r=1m into the equation. dtdV=(31)⋅π⋅2⋅1m⋅10m/s⋅6m.
Final Simplification: Simplify the expression: dtdV=(31)⋅π⋅2⋅10⋅6=40π cubic meters per second.
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