Need Help? Read it Talk to a Tutor 1/3 points |Previous Answers SPreCalc6 1.11.0

Question

Need Help? Read it Talk to a Tutor 1/3 points |Previous Answers SPreCalc6 1.11.041.MI The resistance R of a wire varies directly as its length L and inversely as the square of its diameter d. (a) Write an equation that expresses this joint variation. (Use k for the constant of proportionality.) kL (b) Find the constant of proportionality if a wire 1.2 m long and 0.005 m in diameter has a resistance of 175 ohm k= (c) Find the resistance of a wire made of the same material that is 3 m long and has a diameter of 0.007 m. (Rou ohms Need Help?ead it Watch It Master It Talk to a Tutor /1 points SPreCalc6 1.11.036.MI. e stopping distance D of a car after the brakes have been applied varies directly as the square of the speed s. A certai e maximum speed it can be traveling if it needs to stop in 160 ft? (Round your answer to one decimal place.) mi/h

Explanation / Answer

a) R = kL / d^2

b) plugging the values

175 = k ( 1.2) / (0.005)^2

k = 175 * ( 0.005)^2 / 1.2

k = 7/1920 = 0.0036

c) R = 7/1920 * (3) / 0.007^2

R = 223.2 ohms

Related Questions

Navigate

• Browse (All)
• Browse N
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.