3.9 Homework - Related Rates (Homework)

1. [-11 Points] SCALCETB 3.9.002. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER (a) 1m Is the area or a circle with radius r and the circle expands as time passes, rind fTA in terms mfg. f l 11;! : dr dz dr (b) Suppose oil spills from a ruptured tanker and spreads in a circular pattern. If the radius of the oil spill Increases at a constant rate of 2 m/s, exactly how fast (In mZ/s) Is the area of the spill Increasing when the radius Is 29 m? mZ/s Need Help? 2. [-11 Points] SCALCET9 3.9.003. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Each side of a square is increasing at a rate of 7 Cm/s. At what rate (in cm2/s) is the area of the square increasing when the area Df the square is 25 cm2? Ems Need Help? 3. [I1 Paints] SCALCET9 3.9.010. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Ifx2 +y2 +22: 1%: 9,and%: &,nd%when (x, y, z) : (l, 2, 1). E = Z all: Need Help? _ 4. [I1 Points] SCALCET9 3.9.015. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A street light Is mounted at the top of a 157ft7ta|| pale. A man 6 feet tall walks away from the pole With a speed of 7 Ft/s along a straight path. How fast (In W5) is the Up of his shadow mnvlng when he is 30 feet from the pole? :ms Need Help? 7 _7 5. [-/1 Points] DETAILS SCALCET9 3.9.020. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A baseball diamond is a square with side 90 feet. A batter hits the ball and runs toward first base with a speed of 19 ft/s. 90 ft (a) At what rate (in ft/s) is his distance from second base decreasing when he is halfway to first base? (Round your answer to one decimal place.) ft/s (b) At what rate (in ft/s) is his distance from third base increasing at the same moment? (Round your answer to one decimal place.) ft/s Need Help? Read It