Solving Transformer Problems: Primary and Secondary Coils

  • Thread starter Thread starter kkarapet
  • Start date Start date
  • Tags Tags
    Transformer
Click For Summary
The discussion revolves around solving a transformer problem involving primary and secondary coils with 300 and 804 windings, respectively. The voltage across the secondary coil is calculated to be 56.3 V when the primary coil has a potential difference of 21.0 V. A question arises regarding the effective load resistance of the secondary coil when connected to a 145 Ohm resistor, with confusion about whether this resistance refers to the primary coil or if it involves multiple resistors in the secondary circuit. It is clarified that the task is to find the equivalent resistance reflected back to the primary winding. The solution can be approached using energy conservation principles.
kkarapet
Messages
2
Reaction score
0
Transformer problem, Please Help!

Please help with this problem.

A transformer consists of 300 primary windings and 804 secondary windings.
a) If the potential difference across the primary coil is 21.0 , what is the voltage across the secondary coil ?
Found this part, Vs = 56.3 V

b) If the potential difference across the primary coil is 21.0 V , what is the effective load resistance of the secondary coil if it is connected across a 145 Ohms resistor?

This part I am not getting. Is it saying that 145 Ohms is Rp (Resistance of the primary coil) ??, or there are more than one resistors for the secondary coil and I need to find the Req. Please help!

Homework Statement

 
Physics news on Phys.org
Probably they mean what resistance is reflected back to the primary winding. In other words, what resistance does the 21V source see?

You can deduce the answer from an energy-conservation argument.
 
Thank you!
 

Thread 'Magnitude of buoyant force in fluids of different densities'

The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?
View full post »

Similar threads

Transformer; make primary voltage x10 of the secondary voltage
  • · Replies 4 ·
Replies
4
Views
2K
Transformer question (between substation and home)
  • · Replies 1 ·
Replies
1
Views
1K
Voltage in secondary coil of transformer
  • · Replies 13 ·
Replies
13
Views
3K
The efficiency of a transformer
  • · Replies 5 ·
Replies
5
Views
3K
What Happens to Primary Voltage if 8V is Applied to Secondary Coil?
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad Can a One Direction Transformer Prevent Reverse Induction in Primary Coil?
  • · Replies 21 ·
Replies
21
Views
2K
Transformer windings and voltage
  • · Replies 2 ·
Replies
2
Views
2K
I Don't Understand Transformers/How to Apply Them
  • · Replies 81 ·
3
Replies
81
Views
8K
Finding efficiency between transformers.
  • · Replies 3 ·
Replies
3
Views
3K
Brightness of lamp connected to transformer
  • · Replies 17 ·
Replies
17
Views
4K