Assuming there are no choices, the answer might be the practice of calling upon gods and goddesses to help the sick.
Answer:
0.9999986*c
Explanation:
The ship would travel 2.54*10^7 light years, which means that at a speed close to the speed of light the trip would take 2.54*10^7 years from the point of view of an observer on Earth. However from the point of view of a passenger of that ship it will take only 70 years if the speed is close enough to the speed of light.

Where
Δt is the travel time as seen by a passenger
Δt' is the travel time as seen by someone on Earth
v is the speed of the ship
c is the speed of light in vacuum
We can replace the fraction v/c with x






It would need to travel at 0.9999986*c
Answer:
- 4.2 kJ
Explanation:
We shall find out the initial temperature of the gas
PV / T = n R
20 X 10³ X .26 / T = 9 X 8.3
T = 69.6 K
Since the pressure of gas is constant
V / T = constant
V₁ / T₁ = V₂ / T₂
.26 / 69.6 = .12 / T₂
T₂ = 32.12 K
gas is cooling so there will be decrease in internal energy
Change in temperature = 69.6 - 32.12
= 37.48 K.
decrease in internal energy
= - n Cv x fall in temperature
= - 9 x 1.5 x 8.31 x 37.48 ( Cv = 1.5 R given )
= - 4.2 kJ .
Answer:
The potential energy increases if the orbital radius increases.
Explanation:
The orbital radius of the electron increases means the distance from the nucleus of the hydrogen atom increase.
The nucleus is positively charged .
The potential energy is given by P.E = -
where Z is the atomic number
r is the radius
The negative sign indicates that the electron which is revolving is bound to nucleus.
As the radius and potential energy are inversely proportional it is clear that when <em>radius increase</em> the<em> potential energy become less negative </em>which means the potential energy increases when the orbital radius increase.