Paper 3 Alternating Current Generators Drills

Q1 Generator Design

A generator is redesigned by doubling the number of turns and increasing rotation frequency by $50\%$, while $B$ and $A$ remain unchanged.

1. State how the output frequency changes. [1]
2. Determine the factor by which peak emf changes. [2]
3. Explain the energy transfer involved when the generator supplies a load. [3]

Q2 Quarter-Turn Map

1. Describe how flux linkage changes over one full rotation. [3]
2. Relate the sign of induced emf to the gradient of the flux-linkage graph. [3]
3. Explain why a larger load current makes the generator harder to turn. [2]