Technical Mathematics, Sixth Edition

17.7. CHAPTER 17 REVIEW PROBLEMS

1. If y varies inversely as x, and y is 736 when x is 822, find y when x is 583. 1040

2. If y is directly proportional to the power of x, by what factor will y change when x is tripled? 15.6

3. If y varies jointly as x and z, by what percent will y change when x is increased by 15.0% and z is decreased by 4.00%? 10.4% increase

4. The braking distance of an automobile varies directly as the square of the speed. If the braking distance of a certain automobile is 34.0 ft at 25.0 mi/h, find the braking distance at 55.0 mi/h. 165 ft

5. The rate of flow of liquid from a hole in the bottom of a tank is directly proportional to the square root of the liquid depth. If the flow rate is 225 L/min when the depth is 3.46 m, find the flow rate when the depth is 1.00 m. 121 L/min

6. The power needed to drive a ship varies directly as the cube of the speed of the ship, and a 77.4-hp engine will drive a certain ship at 11.2 knots. Find the horsepower needed to propel that ship at 18.0 knots. 321 hp

7. If the tensile strength of a cylindrical steel bar varies directly as the square of its diameter, by what factor must the diameter be increased to triple the strength of the bar? 1.73

8. The life of an incandescent lamp varies inversely as the 12th power of the applied voltage, and the light output varies directly as the 3.5th power of the applied voltage. By what factor will the life increase if ...