An alien civilization has sent a small Spherical bot, made of Sterling Silver,
fitted with a light emitter and sensor as depicted below, towards a black hole
to explore the region around it. The bot moves slowly towards the black hole,
radially into it. The light source emits light in such a way that it
is tangential (at
the pt. of emission) to a circle with ‘centre of black hole’ as its
centre, and the
distance between the black hole and the centre of the bot as its radius. The
region around the black hole is free of dust or any other obstacle, and there
are no other light sources anywhere nearby which can be perceived by the
Due to some malfunction, the sensor of the bot receives only those signals,
which fall onto it radially.
What will be the last thing that the sensor records before it perceives the
blackness of the black hole?
NOTE : The effect of gravity of any other bodies other than the black hole on
the bot is negligible
The Attempt at a Solution
As light bends around the black hole, there would be two rays coming to the sensor , thus forming double image of the surrounding stars.... as it could receive signals only in radial direction, is it a single image of the surrounding stars?
Am I moving in the right direction or going wrong somewhere?
Please come up with a different solution (if any)
Umm....Sorry if am asking silly questions but try to answer them as am really a beginner :)