Ask Question
23 March, 13:54

You're a safety engineer reviewing plans for a university's new high-rise dorm. The elevator motors draw 20 A and behave electrically like 2.6-H inductors. You're concerned about dangerous voltages developing across the switch when a motor is turned off, and you recommend that a resistor be wired in parallel with each motor.

1) What should be the resistance in order to limit the emf to 70 V?

2) How much energy will the resistor dissipate?

+5
Answers (1)
  1. 23 March, 15:12
    0
    a) R ' = 3.5 ohms

    b) energy decipated = 560J

    Explanation:

    V = I. R

    R = V / I

    R ' = 70 / 20

    R ' = 3.5 ohms

    2) energy decipated = 1/2ij²

    energy decipated = 1/2 x 2.8 x (20) ²

    energy decipated = 560J
Know the Answer?
Not Sure About the Answer?
Find an answer to your question ✅ “You're a safety engineer reviewing plans for a university's new high-rise dorm. The elevator motors draw 20 A and behave electrically like ...” in 📘 Physics if you're in doubt about the correctness of the answers or there's no answer, then try to use the smart search and find answers to the similar questions.
Search for Other Answers