5.6.2 Electromagnetic Effects (transformers)

Transformers
> Device used to c__ the size of alt. v__ or alt. c__
o   Achieved via the g__ effect

change, voltage, current, generator

Why do transformers only work with AC

needs changing magnetic field

which side is primary

left

which side is secondary

right

primary coil provides __

ac

soft iron core is used as it’s easily m__

magnetised

secondary coil is the o__

output

1. a_ supplied
2. const c__ m__ field in iron core → 2nd coil
3. e__ induced
4. if complete circuit, current is i__

ac, changing magnetic, emf, induced

Step up transformers will __ V

incr

Step down transformers will __ V

decr

N__ < N__

Np, Ns

N__ < N__

Ns, Np

V__/V__ = N__/N__
(N = # of turns)

Vp/Vs = Np/Ns

I_V_ = I_V_ (for 100% eff. transformer)

IpVp = IsVs

Adv of high voltage
> bc of V = __, ↑V = ↓_ = ↓t__ energy wasted
> c__/thinner cables can be used = less cost

IR, I, thermal, cheaper