First we have to calculate the volume of the living room:
V = L x W x H = 4.5 m * 3.4 m * 2.9 m
V = 44.37 m³
We know that Density = 1.29 kg/m²
D = m / V
m = D · V
m = 1.29 kg/m³ · 44.37 m³
m = 57.2373 kg ≈ 57.2 kg
Answer: The approximate mass of air in living room is 57.2 kg.
I believe the correct answer is atmosphere (D).
Answer:
124.86 V
Explanation:
We have to first calculate the voltage drop across the copper wire. The copper wire has a length of 358 ft
1 ft = 0.3048 m
358 ft = 109.12 m
The diameter of 2 AWG copper wire (d) = 6.544 mm = 0.006544 m
The area of the wire = πd²/4 = (π × 6.544²)/4 = 33.6 mm²
Resistivity of wire (ρ) = 0.0171 Ω.mm²/m
The resistance of the wire = 
The voltage drop across wire = current * resistance = 6.1 A * 0.056 ohm = 0.34 V
The voltage at end = 125.2 - 0.34 = 124.86 V
Answer:
If the rifle is held loosely away from the shoulder, the recoil velocity will be of -8.5 m/s, and the kinetic energy the rifle gains will be 81.28 J.
Explanation:
By momentum conservation, <em>and given the bullit and the recoil are in a straight line</em>, the momentum analysis will be <em>unidimentional</em>. As the initial momentum is equal to zero (the masses are at rest), we have that the final momentum equals zero, so

now we clear
and use the given data to get that

<em>But we have to keep in mind that the bullit accelerate from rest to a speed of 425 m/s</em>, then <u>if the rifle were against the shoulder, the recoil velocity would be a fraction of the result obtained</u>, but, as the gun is a few centimeters away from the shoulder, it is assumed that the bullit get to its final velocity, so the kick of the gun, gets to its final velocity
too.
Finally, using
we calculate the kinetic energy as
