There is a current of 8.0 A in a straight wire. The current is changed to 4.0 A in the opposite direction. Which effect does this have on the magnetic field around the wire?
It decreases in strength and acts in the opposite direction.
It decreases in strength and acts in the same direction.
It increases in strength and acts in the opposite direction.
It increases in strength and acts in the same direction.
30 exam-style questions on CIE IGCSE Physics 4.5.3a Magnetic effect of a current and its applications. Each one has a worked solution and a mark scheme showing where the marks go.