Two coils are close together but are not electrically connected. The first coil is connected to a direct-current supply and a switch. The second coil is connected to an oscilloscope.
The switch is closed. After a short time, the current in the first coil becomes constant.
Which statement describes the oscilloscope trace once the current is constant?
It returns to zero because the magnetic field through the second coil stops changing.
It reverses direction because the current in the first coil has stopped increasing.
It keeps rising because a current is still flowing through the first coil.
It stays at a steady value that is not zero because the first coil still produces a magnetic field.
92 exam-style questions on Edexcel GCSE Physics 13.1 Inducing a current, covering 13.1.1 Producing an electric current by induction, 13.1.2 Factors affecting the induced potential difference, 13.1.3 Alternators and dynamos, and 13.1.4 Microphones and loudspeakers. Each one has a worked solution and a mark scheme showing where the marks go.