The Blimp Problem
note
Suppose that a certain clock has a minute hand that is 4 inches long and an hour hand that is 3 inches long. What is the rate of change of the distance between the tips of the minute and hour hands at 2:00?
−16.6 inches / hour
Laura is hitting a golf ball at the driving range. Suppose that the altitude of the ball is given in feet by the equation y = 200t − 40t ^2, where t is the time in seconds after she hits the ball. Suppose also that the horizontal velocity of the ball is constant and equal to 80 feet per second. At what rate is the angle of elevation of the ball changing 2 seconds after Laura hits the ball?
−0.15 radians / second
Two cars leave an intersection at the same time, one headed west and the other north. The westbound car is moving at 40 mph and the northbound car is moving at 50 mph. Fifteen minutes later, what is the rate of change in the perimeter of the right triangle created using the two cars and the intersection?
154.02 mph
An object is moving along the graph of the curve x^2y^2/2x−y=1. At a particular moment, the particle is at (1,1) and dx/dt=5. Find the value of dy/dt at this moment.
0
A spherical balloon is being inflated from a compressor. Suppose the volume of the balloon is increasing at a constant rate of 10 cubic inches per second. At what rate is the surface area of the balloon increasing when its radius is 6 inches?
3.3 square inches per second