Related Rates in a Water Tank: Finding the Rate of Change of Water Depth

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SUMMARY

The discussion focuses on solving a related rates problem involving an inverted right-circular cone water tank with a radius of 15 meters and a depth of 12 meters. Water enters the tank at a rate of 2 cubic meters per minute, and the goal is to determine how fast the water depth increases when the depth is 8 meters. The volume of the cone is given by the formula V=(1/3)(π)(r²)(h). To solve for the rate of change of height (dh/dt), the relationship between the radius and height must be established, allowing for the elimination of the radius variable in favor of height.

PREREQUISITES
  • Understanding of related rates in calculus
  • Familiarity with the volume formula for cones, V=(1/3)(π)(r²)(h)
  • Knowledge of differentiation techniques
  • Ability to manipulate geometric relationships in calculus problems
NEXT STEPS
  • Study the concept of related rates in calculus
  • Learn how to derive relationships between variables in geometric shapes
  • Practice solving similar problems involving cones and cylinders
  • Explore the application of implicit differentiation in related rates problems
USEFUL FOR

Students studying calculus, particularly those focusing on related rates, as well as educators seeking examples for teaching geometric applications in calculus.

b.mueller5
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Homework Statement


A water tank has the shape of an inverted right-circular cone, with radius at the top 15 meters and depth 12 meters. Water is flowing into the tank at rate of 2 cublic meters per minute. How fast is the depth of water in the tank increasing at the instant when the depth is 8 meters


Homework Equations


V=(1/3)(pi)(r^2)(h)

The Attempt at a Solution


dv/dt=2 meter^3/min
dv/dt=(1/3)(pi)(2rh(dr/dt)+(r^2)(dh/dt))
but that has 2 unknow varibles in it.
 
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You need to relate the radius in terms of the height of the cone since both are changing with respect to time and because you only know the rate of change of the height. Once you do this, you will be able to differentiate it since you know the rate of change of the height. Try to find a way to relate the radius in terms of height. With this information can you figure out how to get rid of r and put it in terms of h?
 
Yeah thanks that helps a lot
 

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