# P.d. increases in a step up transformer

1. Nov 16, 2008

### sachin123

just tell me how the p.d. increases in a step up transformer.
(Please dont use formulas for this.)
if we take a conductor of same length and thickness as the 1st one for the secondary coil,
the voltage doesn't increase.
but why does it,if we increase the length.
I mean,how can that affect it?
(Please dont use formulas for this,because i want to see how the formula is derived than the other way round)

and how does it satisfy the law of energy conservation?
Thank You.

2. Nov 16, 2008

### pallidin

Re: Transformers

Remember that, as the potential difference increases, the current decreases.
Thus the power remains the same(minus loses in the transformation)

3. Nov 16, 2008

### sachin123

Re: Transformers

again:

if we take a conductor of same length and thickness as the 1st one for the secondary coil,
the voltage doesn't increase.
but why does it,if we increase the length.
I mean,how can that affect it?
(Please dont use formulas for this,because i want to see how the formula is derived than the other way round)
Please tell me how(physically)the length of Secondary Coil affects emf??!??

4. Nov 16, 2008

### sachin123

Re: Transformers

Please apply simple proportionality rather formulas.
Please tell me how(physically)the length of Secondary Coil affects emf??!??

5. Nov 16, 2008

### Phrak

Re: Transformers

The length and wire diameter don't determine the votlage. The number of turns do.
The ratio of turns is equal to the ratio of the voltages.

6. Nov 17, 2008

### cabraham

Re: Transformers

The length of the secondary winding does not determine secondary emf. Rather, the flux density and secondary number of turns does. The flux density is determined by the primary voltage source, the frequency, the core area, and the primary no. of turns. This flux then couples the secondary winding. The secondary no. of turns (encirclements of the flux) and the magnitude of the flux density, determines the secondary emf.

Does this help?

Claude