Pregnancy lasts approximately 9 weeks (63 days) in the cat. However, it is not possible to detect pregnancy during the first 3 weeks. An experienced veterinarian may be able to palpate or feel the fetuses in the uterus of a relaxed cat, as the optimal time for pregnancy palpation is about 28-32 days of pregnancy.
Answers. Relevance. Rating Newest Oldest. The speed of electromagnetic waves in vacuum is the speed of light in vacuum because light is an electromagnetic wave: c = 299,792,458 meters per second, exactly (0.670617 billion mph).
In a vacuum, all electromagnetic waves travel at approximately 3 x 108 m/s - the fastest speed possible. When electromagnetic waves travel through matter (for example, light through air or glass), they travel a bit slower than this but rarely less than half as fast as in a vacuum. The value for light travelling through an optical fibre, for example, is taken as 2 x 108 m/s.