Hi Everyone I'm new to the forum, and decided to join because a question on physics is playing with my head

"When the sun is directly overhead, a narrow shaft of light enteres a small hole in the ceiling of a room. The ceiling is flat and is 10m above the floor. A bright spot moves across the floor below at the seem of V cm.s^-1."

Q1 is fairly simple - calculate V

v = rw where r is radius and w is angular velocity..

v = 10m * (2*pi / 24 * 60 * 60)

v ~ .073 cm/s.

The second part to the question states:

"The room has a polished floor and the beam of light is reflected onto the roof. At which speed does the dot move on the ceiling?"

- The answer + solution they provide is 2 * V. Because v = rw, and since r is no longer 10m but 20m (the light travels twice as far)..

THIS doesn't make sense to me? woudln't the velocity of the light move across the ceiling at the same speed as the on the floor? i'd understand if the room was 20m from floor to ceiling but this is a reflection?

Thank you in advance