Electrical Energy Dissipation Across Resistors

  • Thread starter Yosty22
  • Start date
  • #1
185
4

Homework Statement



(image attached)
A). What is the total rate at which electrical energy is dissipated in the 5.0−Ω resistor?
B). What is the total rate at which electrical energy is dissipated in the 9.0−Ω resistor?
C). What is the power output of the 16.0-V battery?
D). At what rate is electrical energy being converted to other forms in the 8.0-V battery?


Homework Equations



P=V_ab(I)=I^2R=V_ab^2/R

The Attempt at a Solution



I can't figure this out at all. For part A, I need the voltage difference and the resistance. How would I find the voltage difference? And does the 5 ohm resistor mean that the resistance is 5 over the resistor? In which case I need to find the voltage drop across the resistor. How do I do this?
 

Answers and Replies

  • #2
phinds
Science Advisor
Insights Author
Gold Member
16,734
7,418
no image attached
 
  • Like
Likes 1 person
  • #4
phinds
Science Advisor
Insights Author
Gold Member
16,734
7,418
Just sum up all of the voltage sources around the loop and all the resistances, since they're all in series, and you'll have the current around the loop. Can you take it from there?
 
  • #5
185
4
Ok, so I added up the voltages (24V) and added up the resistance (17 ohms). I then did V/R to get I=1.412A. Then, I used the equation P=V_ab * I and got P=120W, but it is wrong. What am I doing here?
 
  • #6
phinds
Science Advisor
Insights Author
Gold Member
16,734
7,418
You are not taking into account the direction of the voltages.
 

Related Threads on Electrical Energy Dissipation Across Resistors

  • Last Post
Replies
3
Views
3K
  • Last Post
Replies
3
Views
16K
  • Last Post
Replies
16
Views
1K
  • Last Post
Replies
13
Views
4K
Replies
6
Views
6K
  • Last Post
Replies
4
Views
14K
  • Last Post
Replies
3
Views
444
Replies
1
Views
5K
Replies
2
Views
21K
Replies
3
Views
3K
Top