Amber reflective studs on a UK motorway are found along the right-hand edge of the carriageway, next to the central reservation (the barrier or strip separating traffic going in opposite directions).

Quick Scoop

  • They run between the main carriageway and the central reservation.
  • They mark the right-hand edge of the motorway to stop you drifting toward the central reservation, especially in the dark or in poor weather.
  • Other colours mean different things (for context): red on the left edge, white between lanes, green at slip roads and lay-bys.

So if your theory test asks “Where are amber reflective studs found on a motorway?” , the correct idea is:
Along the right-hand edge of the carriageway, next to the central reservation.

TL;DR: Amber reflective studs = right-hand edge of the motorway, beside the central reservation, guiding you away from oncoming traffic.

Information gathered from public forums or data available on the internet and portrayed here.