• Support PF! Buy your school textbooks, materials and every day products Here!

Very basic Physics questions!

  • Thread starter LitKey
  • Start date
  • #1
3
0
Might be some simple questions for you guys but I'm just in grade 9

1. Do isolating transformers change the voltage in a circuit?

What I know is that isolating transformers have the same amount of coils because it needs to be safe.

2. Explain why an isolating transformer is often used in a bathroom shaver circuit.

3. A transformer has 5000 tunrs on its primary coil, and 8000 tunrs on its secondary coil.
If the input voltage is 230 V, find the output voltage.

- Lit
 

Answers and Replies

  • #2
berkeman
Mentor
57,505
7,528
Might be some simple questions for you guys but I'm just in grade 9

1. Do isolating transformers change the voltage in a circuit?

What I know is that isolating transformers have the same amount of coils because it needs to be safe.

2. Explain why an isolating transformer is often used in a bathroom shaver circuit.

3. A transformer has 5000 tunrs on its primary coil, and 8000 tunrs on its secondary coil.
If the input voltage is 230 V, find the output voltage.

- Lit
Welcome to the PF.

You will need to show more of your work on #2 and #3 before we can help you. That's how we handle Homework Help here at the PF.

For #1, you are mostly correct. In general, an "isolation" transformer will be a 1:1 transformer, with the main talk of galvanically insulating the primary from the secondary. However, an "isolating" transformer just means that the primary is insulated from the secondary, so the turns ratio could be whatever is needed for the application.

Please give us your thoughts on #2 and #3. For #3, what is the voltage ratio equation for a transformer, in terms of the ratio of the number of turns primary/secondary?
 
  • #3
3
0
Might be some simple questions for you guys but I'm just in grade 9

1. Do isolating transformers change the voltage in a circuit?

What I know is that isolating transformers have the same amount of coils because it needs to be safe.

2. Explain why an isolating transformer is often used in a bathroom shaver circuit.

3. A transformer has 5000 turns on its primary coil, and 8000 turns on its secondary coil.
If the input voltage is 230 V, find the output voltage.

- Lit
Welcome to the PF.

You will need to show more of your work on #2 and #3 before we can help you. That's how we handle Homework Help here at the PF.

For #1, you are mostly correct. In general, an "isolation" transformer will be a 1:1 transformer, with the main talk of galvanically insulating the primary from the secondary. However, an "isolating" transformer just means that the primary is insulated from the secondary, so the turns ratio could be whatever is needed for the application.

Please give us your thoughts on #2 and #3. For #3, what is the voltage ratio equation for a transformer, in terms of the ratio of the number of turns primary/secondary?
My thoughts for #2 is that if its used for a bathroom shaver circuit, it needs to be very safe so that no harm can be procured in our face. Not sure if thats quite the answer though because the question says "explain". This is just 2 sentences.

#3. I can give you a short summary. If its a step down transformer with a 4 to 1 turns ratio, and the input voltage is 480, the output would be 120. So you're dividing with 4. As you do with the primary and secondary coil. I think a step up transformer would be the other way around. 1 to 4 turns = (1x4 = 4.) 120V and 480V. (120Vx4 = 480V.)

And for #1, if I understood right, the voltage doesn't change due to safety reasons. You, yourself choose a permanent voltage and change it manually.
 
  • #4
berkeman
Mentor
57,505
7,528
My thoughts for #2 is that if its used for a bathroom shaver circuit, it needs to be very safe so that no harm can be procured in our face. Not sure if thats quite the answer though because the question says "explain". This is just 2 sentences.

#3. I can give you a short summary. If its a step down transformer with a 4 to 1 turns ratio, and the input voltage is 480, the output would be 120. So you're dividing with 4. As you do with the primary and secondary coil. I think a step up transformer would be the other way around. 1 to 4 turns = (1x4 = 4.) 120V and 480V. (120Vx4 = 480V.)

And for #1, if I understood right, the voltage doesn't change due to safety reasons. You, yourself choose a permanent voltage and change it manually.
You have the turns ratio equation correct for #3, so now put in the turns numbers that they list, and calculate the output voltage answer for #3.
 
  • #5
3
0
Alright, I'll do that in a min. But is my answers for #1 and #2 correct?
 

Related Threads on Very basic Physics questions!

Replies
5
Views
407
  • Last Post
Replies
3
Views
2K
Replies
3
Views
3K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
2
Views
6K
  • Last Post
Replies
5
Views
8K
  • Last Post
Replies
16
Views
812
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
13
Views
2K
  • Last Post
Replies
2
Views
1K
Top