David Sang Solutions for Chapter: Electromagnetic Induction, Exercise 3: Questions

Why is electrical power transmitted in the grid at high voltage?

Name the three essential parts of a transformer.

A transformer has $100$ turns on the primary coil and $1000$ on the secondary. Is it a step-up or a step-down transformer?

A portable radio has a built-in transformer so that it can work from the mains instead of batteries. Is this a step-up or step-down transformer?

A step-up transformer has $2000$ turns on one coil and $5000$ on the other. Calculate the ratio $\frac{N_P}{N_S}$ for this transformer.

A transformer is designed to provide $20 \mathrm{V}$ from a $240 \mathrm{V}$ supply. If the primary coil has $1200$ turns, how many turns must the secondary have?