Answer:
Einstein's general theory of relativity is the theory behind black holes has been tested with a wide range of experiments of which all confirm the predictions the theory makes. We cannot see black holes phenomena inside the event horizon, we do observe things outside this limit.
Black holes in binary star systems leave signs of their presence on neighboring star thats detected and the signs include X-ray emissions, accretion disks, and large orbit perturbations.
this is the evidence that astronomers and physicists have to show that the theory about black holes is correct.
Answer:
C. 28.09 amu
Explanation:
The natural occurring element exist in 3 isotopic forms: namely X-28 (27.977 amu, 92.23% abundance), X-29 (28.976 amu, 4.67% abundance) and X-30 (29.974 amu, 3.10% abundance).
The atomic weight of elements depends on the isotopic abundance. If you know the fractional abundance and the mass of the isotopes the atomic weight can be computed.
The atomic weight is computed as follows:
atomic weight = mass of X-28 × fractional abundance + mass of X-29 × fractional abundance + mass of X-30 × fractional abundance
atomic weight = 27.977 × 0.9223 + 28.976 × 0.0467 + 29.974 × 0.0310
atomic weight = 25.8031871 + 1.3531792 + 0.929194
atomic weight = 28.0855603 amu
To 2 decimal place atomic weight = 28.09 amu
Answer:
(a) has the highest frequency
Explanation:
E = hf...where E(is the energy of a photon);h(is the planck's constant) and f is the frequency of the photon
Whereby this formula shows us that energy of a photon is directly proportional to its frequency
So hence if the energy is high then the frequency of the photon is also high
Velocity = displacement (distance)/time
v=80m/4s
v=20m/s
velocity = 20 meters per second
The freezing point ..... :)