Ask Question
2 April, 00:06

When the voltage across a steady resistance is doubled, the current?

+4
Answers (1)
  1. 2 April, 00:27
    0
    I'm actually going ahead in the book (DC Circuits) so this isn't really homework but I figured the tag was appropriate ... the name of the chapter is Ohm's Law and Watt's Law.

    Problem: Calculate the power dissipated in the load resistor, R, for each of the circuits. Circuit (a) : V = 10V; I = 100mA; R = ?; Since I know V and I use formula P = IV: P = IV = (100mA) (10V) = 1 W.

    The next question is what I'm not sure а bout:

    Question: What is the power in the circuit (a) above if the voltage is doubled? (Hint: Consider the effect on current).

    What I did initially was: P = IV = (100mA) (2V) = 2 W

    But then I looked at the answer and it said 4 W, then I looked at the Hint again. Then I remembered in the book early on it said "If the voltage increases across a resistor, current will increase."

    So question is: When solving problems I have to increase (or decrease) current (I) every time voltage (V) is increased (decreased) in a problem, right? How about the other way around, when increasing current (I), you need to increase voltage (V). I'm pretty sure that's how they got 4 W, but want to make sure before I head to the next section of the book.

    P = IV = (200mA) (2V) = 4 W
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “When the voltage across a steady resistance is doubled, the current? ...” in 📗 Physics if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers