In Searle’s apparatus, when experimental wire is loaded and unloaded, the air bubble in spirit level gets shifted.

Options

• Option A

  towards reference wire while loading and towards experimental wire while unloading

• Option B

  towards experimental wire while loading and towards reference wire while unloading

• Option C

  towards experimental wire, both the times, during loading and unloading

• Option D

  towards reference wire, both the times during loading and unloading