Answer:
The era of planet formation ended when the remaining hydrogen and helium gas of the solar nebula was swept into interstellar space by the solar winds.
Explanation:
The Solar System is formed from a molecular cloud (compound by gas and dust). If there is a near perturbation to the cloud, maybe due to a supernova explosion, the molecular cloud will collapse under its own gravity. Then, in some point it starts to rotate and will accrete all the material in a disk around the protostar¹.
Inside the disk, dust particles start to collide and accrete until they form planetesimals². As a consequence of the gravitational force of the star, rocky and metallic particles will be more attracted to the inner part of the Solar System (close to the Sun) since they have more mass than gas.
Then, when the star has the necessary pressure and temperature to initiate nuclear reactions in its core, it will be able to emit huge amounts of energy, better known as solar winds. These winds will expel gas (hydrogen and helium) from the Solar System more easily than the rocky and metallic particles.
Notice that when such event occurs, rocky and gaseous planets were already formed.
Key terms:
¹Protostar: A young star.
²Planetesimals: Object formed by many fragments due to the gravitational attraction between them.
Answer:
9.965 nF
Explanation:
The capacitance of the axon C = εA/d where ε = dielectric constant = 24.78 × 10⁻¹² F/m, A = surface area of axon = 2πrL where r = radius of axon = 8 μm = 8 × 10⁻⁶ m and L = length of axon = 8 cm = 8 × 10⁻² m and d = thickness of membrane = 0.01 μm = 0.01 × 10⁻⁶ m
So, C = εA/d
C = ε2πrL/d
Substituting the of the values variables into the equation, we have
C = ε2πrL/d
C = 24.78 × 10⁻¹² F/m × 2π × 8 × 10⁻⁶ m × 8 × 10⁻² m/0.01 × 10⁻⁶ m
C = 9964.63 × 10⁻²⁰ Fm/0.01 × 10⁻⁶ m
C = 996463 × 10⁻¹⁴ F
C = 9.96463 × 10⁻⁹ F
C = 9.96463 nF
C ≅ 9.965 nF
I use the impulse momentum formula.
the 4.0 kilogram ball requires more force to stop
Answer:
(B) The total internal energy of the helium is 4888.6 Joules
(C) The total work done by the helium is 2959.25 Joules
(D) The final volume of the helium is 0.066 cubic meter
Explanation:
(B) ∆U = P(V2 - V1)
From ideal gas equation, PV = nRT
T1 = 21°C = 294K, V1 = 0.033m^3, n = 2moles, V2 = 2× 0.033=0.066m^3
P = nRT ÷ V = (2×8.314×294) ÷ 0.033 = 148140.4 Pascal
∆U = 148140.4(0.066 - 0.033) = 4888.6 Joules
(C) P2 = P1(V1÷V2)^1.4 =148140.4(0.033÷0.066)^1.4= 148140.4×0.379=56134.7 Pascal
Assuming a closed system
(C) Wc = (P1V1 - P2V2) ÷ 0.4 = (148140.4×0.033 - 56134.7×0.066) ÷ 0.4 = (4888.6 - 3704.9) ÷ 0.4 = 1183.7 ÷ 0.4 = 2959.25 Joules
(C) Final volume = 2×initial volume = 2×0.033= 0.066 cubic meter
Answer:
D
Explanation:
The reproduction parts of the plant are in the flower and around it so this would eliminate the plants ablity to reproduce.
