Problem 1 :
An airplane is flying towards a radar station at a constant height of 6 km above the ground. If the distance s between the airplane and the radar station is decreasing at a rate of 400 km per hour when s = 10 km, what is the horizontal speed of the plane ?
Problem 2 :
A light is on the ground 20 m from building. A man 2 m tall walks from the light directly toward the building at 1 m/s. How fast is the length of his shadow on the building changing when he is 14 m from the building ?
Problem 3 :
A conical cup is 4 cm across and 6 cm deep. Water leaks out of the bottom at the rate of 2 cm3/sec. How fast is the water dropping when the height of the water is 3 cm?
Problem 4 :
Air is escaping from a spherical balloon at the rate of 2 cm3 per minute. How fast is the surface area shrinking when the radius is 1 cm?
V = 4/3 πr3 and S = 4πr2
where V is the volume and S is the surface area, r is the radius.
Problem 5 :
A funnel in the shape of an inverted cone is 30 cm deep and has a diameter across the top of 20 cm. Liquid is flowing out of the funnel at the rate of 12 cm3 /sec. At what rate is the height of the liquid decreasing at the instant when the liquid in the funnel is 20 cm deep?
Problem 6 :
Find the rate of change of the area A, of a circle with respect to its circumference C.
Problem 7 :
A boat is being pulled into a dock by attached to it and passing through a pulley on the dock, positioned 6 meters higher than the boat. If the rope is being pulled in at a rate of 3 meters/sec, how fast is the boat approaching the dock when it is 8 meters from the dock?
1) dx/dt = -500 k/hr
2) dh/dt = -10/9 m/s
3) dh/dt = -2/π cm/s
4) dS/dt = -4π cm2/min
5) dh/dt = 27/100π cm/sec
6) dA/dC = C/2π
7) dx/dt = (-15/4) m/sec
May 21, 24 08:51 PM
May 21, 24 08:51 AM
May 20, 24 10:45 PM