Chapter 5.5, Problem 45E

The resistance of a copper wire carrying an electrical current is directly proportional to its length and inversely proportional to its cross-sectional area. A copper wire with a diameter of 0.0126inch has a resistance of 64.9ohms per thousand feet. What length of 0.0201-inch-diameter copper wire will produce a resistance of 33.5ohms?

Solve the following application problem. The distance a body falls varies directly as the square of the time it falls. If an object falls 64 feet in 2 seconds, how long will it take to fall 256 feet?

Automobile collisions The energy dissipated in an auto mobile collision varies directly with the square of the speed. By what factor does the energy increase in a 50-mph collision compared with a 20-mph collision?

At the start of a trip, the odometer on a car read 21,395. At the end of the trip, 13.5 hours later, the odometer read 22,125, Assume the scale on the odometer is in miles. What is the average speed the car traveled during this trip?

Write a report summarizing your findings. When writing the report consider that medical staff estimate that a difference of 4.5 microns or more could impact on their ability to interpret eye pressure correctly.

How do you get volume

Using mental math and your understanding of fundamental units, approximate the area of a regulation basketball court.Describe the process you used to arrive at your final approximation.

You plan to calculate the area of a long, thin rectangle from measurements of its length and width. Which dimension should you measure more carefully? Give reasons for your answer.

table below shows the relationship between the side length of a square and its area. Complete the table. Side Length (inches) Area (square inches) 1 1 4 3. 4 8. 12 b) Are these two quantities proportional? Why or why not?