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A ladder 5m long is leaning against a wall. The bottom of the ladder is pulled along the ground, away from the wall, at the rate of   2 cm  s -2 . How fast is its height on the wall decreasing when the foot of the ladder is 4m away from the wall?

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Important Questions on Application of Derivatives

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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
Using differentiation, approximate value of fx=x2-2x+1 at x=2.99 is ….
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
A ladder of 5 m long rests against a vertical wall with the lower end on the horizontal ground. The lower end of the ladder is pulled along the ground away from the wall at the rate 3 m/sec. The height of the upper end (in meters) while it is descending at the rate of 4 m/sec, is
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
If the volume of a spherical ball is increasing at the rate of 4π cc/sec then the rate of increase of its radius in cm/sec, when the volume is 288π cc is 
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Mathematics>Differential Calculus>Application of Derivatives>Rate of Change of Quantities
A man 6 ′ tall moves away from a source of light 20 ′ above the ground level, his rate of walking being 4m/h. At what rate is the tip of his shadow moving?