Physics, 14.12.2019 06:31 jjjjjjjbvhnchjkj
Imagine an alternative universe where the characteristic decay time of neutrons is 3 min instead of 15 min. all other properties remain unchanged from what was discussed in class.
(a) show that the maximum possible value of the primordial helium fraction is: ymax = 2f 1 + f (1) where f = nn/np ≥ 1 is the neutron-to-proton ratio at the time of nucleosynthesis. prove that this assertion is true.
(b) estimate the maximum fraction of the baryonic matter in the form of helium today. you may assume all he nuclei exist in the form of helium 4
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Which feature of a heating curve indicates a change ofn state
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Atotal charge of –6.50 µc is uniformly distributed within a sphere that has a radius of 0.150 m. what is the magnitude and direction of the electric field at 0.300 m from the surface of the sphere? a) 2.89 × 105 n/c, radially inward b) 6.49 × 105 n/c, radially outward c) 4.69 × 105 n/c, radially inward d) 9.38 × 105 n/c, radially outward e) 1.30 × 106 n/c, radially inward
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Physics, 22.06.2019 10:30
The freezing and boiling point of a substance changes as the air pressure around it changes. for example, at a lower air pressure (higher altitude) it is easier for water molecules to escape from liquid into the air. in a high altitude city such as denver, colorado compared to a sea-level city such as houston, texas, water
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Physics, 22.06.2019 12:30
Awheel of mass 48 kg is lifted to a height of 0.8 m. how much gravitational potential energy is added to the wheel? acceleration due to gravity is g = 9.8 m/s2. a. 30.4 j b. 3.1 j c. 297.9 j d. 11,321 j
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