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).
The energy of the wave is in the electric and the magnetic fields of the electromagnetic waves, therefore, require no medium for propagation. In a vacuum, electromagnetic waves travel at the speed of light, which is a constant (2.9979 x 108ms-1). The intensity/strength of the electric field and the magnetic field has a constant ratio, and they oscillate in phase (i.e. the peaks and the troughs are occurring at the same time during propagation)