<span>Astronomy is a natural science that studies celestial objects and phenomena. More generally, all astronomical phenomena that originate outside Earth's atmosphere are within the purview of astronomy.
Therefore, the correct answer to the question "Astronomy can best be described as a/an" is "study of objects beyond the Earth's atmosphere."</span>
Answer:
a) t₁ = 4.76 s, t₂ = 85.2 s
b) v = 209 ft/s
Explanation:
Constant acceleration equations:
x = x₀ + v₀ t + ½ at²
v = at + v₀
where x is final position,
x₀ is initial position,
v₀ is initial velocity,
a is acceleration,
and t is time.
When the engine is on and the sled is accelerating:
x₀ = 0 ft
v₀ = 0 ft/s
a = 44 ft/s²
t = t₁
So:
x = 22 t₁²
v = 44 t₁
When the engine is off and the sled is coasting:
x = 18350 ft
x₀ = 22 t₁²
v₀ = 44 t₁
a = 0 ft/s²
t = t₂
So:
18350 = 22 t₁² + (44 t₁) t₂
Given that t₁ + t₂ = 90:
18350 = 22 t₁² + (44 t₁) (90 − t₁)
Now we can solve for t₁:
18350 = 22 t₁² + 3960 t₁ − 44 t₁²
18350 = 3960 t₁ − 22 t₁²
9175 = 1980 t₁ − 11 t₁²
11 t₁² − 1980 t₁ + 9175 = 0
Using quadratic formula:
t₁ = [ 1980 ± √(1980² - 4(11)(9175)) ] / 22
t₁ = 4.76, 175
Since t₁ can't be greater than 90, t₁ = 4.76 s.
Therefore, t₂ = 85.2 s.
And v = 44 t₁ = 209 ft/s.
Answer:
W = - 118.24 J (negative sign shows that work is done on piston)
Explanation:
First, we find the change in internal energy of the diatomic gas by using the following formula:
where,
ΔU = Change in internal energy of gas = ?
n = no. of moles of gas = 0.0884 mole
Cv = Molar Specific Heat at constant volume = 5R/2 (for diatomic gases)
Cv = 5(8.314 J/mol.K)/2 = 20.785 J/mol.K
ΔT = Rise in Temperature = 18.8 K
Therefore,
Now, we can apply First Law of Thermodynamics as follows:
where,
ΔQ = Heat flow = - 83.7 J (negative sign due to outflow)
W = Work done = ?
Therefore,
<u>W = - 118.24 J (negative sign shows that work is done on piston)</u>
Answer:
The distance in kilometers is 4012 ×
km.
Explanation:
We know that the conversion of 1 millimeters is equal to 
meter. And then the conversion of 1 meter is equal to km. Then the conversion of 1 millimeter to km will be
1 mm = m
1 m = km
So, 1 mm = × km = km.
As here the the distance is 4012 mm, then the distance in km will be
4012 mm = 4012 × km.
So the distance is 4012 × km.
Potassium iodide
Molar mass: 166.0028 g/mol
Formula: KI
