William Heathcote Solutions for Chapter: Consequences, Exercise 5: Exercise 5

A transformer has $20$ turns on its secondary coil and a primary coil of $100$ turns that is connected to a voltage of $30 V$ . Is this a step-up or step-down transformer?

A transformer has $20$ turns on its secondary coil and a primary coil of $100$ turns that is connected to a voltage of $30 V$ .  Calculate the voltage of the secondary coil. 

In an experiment, a student wants to use a transformer to convert a primary voltage of $3 V$ a .c. to a secondary voltage of $10 V$ a.c. They have coils with $100, 150, 200, 500, 1,000, 1,500 and 2,000$ turns available to make into the transformer. Which coils should they use?

In an experiment, a student wants to use a transformer to convert a primary voltage of $3 V$ a .c. to a secondary voltage of $10 V$ a.c. They have coils with $100, 150, 200, 500, 1,000, 1,500 and 2,000$ turns available to make into the transformer.  What is the largest and smallest voltage they could generate
with these coils? 

In an experiment, a student wants to use a transformer to convert a primary voltage of $3 V$ a .c. to a secondary voltage of $10 V$ a.c. They have coils with $100, 150, 200, 500, 1,000, 1,500 and 2,000$ turns available to make into the transformer. Why would this not work with a d.c voltage?