3 (a) A student uses a plotting compass to investigate the magnetic field around a wire - Edexcel - GCSE Physics Combined Science - Question 3 - 2019 - Paper 1

To determine the direction of the compass needle when current flows from P to Q, we can use the right-hand grip rule. According to this rule, if you grip the wire with your right hand such that your thumb points in the direction of the current (from P to Q), your fingers will curl around the wire. The direction in which your fingers wrap around the wire indicates the direction of the magnetic field lines. Therefore, the compass needle will point tangentially to these lines.

Assuming the options are A, B, C, and D, we need to identify which one correctly illustrates the compass needle's orientation corresponding to the magnetic field direction induced by the current.