Answer:
B. QC > 0; QH < 0
Explanation:
Given that there are two reservoir of energy.
Sign convention for heat and work :
1.If the heat is adding to the system then it is taken as positive and if heat is going out from the system then it is taken as negative.
2. If the work is done on the system then it is taken as negative and if the work is done by the system then it is taken as positive.
From hot reservoir heat is going out that is why it is taken as negative
From cold reservoir heat is coming inside the reservoir that is why it is taken as positive
That is why the answer will be
,
Answer:
Explanation:
given data:
flow Q = 9 m^{3}/s
velocity = 8 m/s
density of air = 1.18 kg/m^{3}
minimum power required to supplied to the fan is equal to the POWER POTENTIAL of the kinetic energy and it is given as
here 
is mass flow rate and given as
Putting all value to get minimum power
Answer:
vₓ = 20 m/s, v_{y} = -15 m / s
Explanation:
This is a conservation of moment problem, since it is a vector quantity we can work each axis independently
The system is formed by the two drones, so the forces during the crash are internal and the moment is conserved
X axis
Initial moment. Before the crash
p₀ = m₁ v₀ₓ + m₂ v₀ₓ
Final moment. After the crash
p_{fx} = (m₁ + m₂) vₓ
p₀ₓ = 
m₁ v₀ₓ + m₂ v₀ₓ = (m₁ + m₂) vₓ
vₓ = (m₁ + m₂) v₀ₓ / (m₁ + m₂)
vₓ = v₀ₓ = 20 m/s
Y Axis
Initial
p_{oy} = m₁ v_{oy}
Final
p_{fy} = (m₁ + m₂) v_{y}
p_{oy} = p_{fy}
the drom rises and when it falls it has the same speed because there is no friction v_{oy} = -60 m/s
m₁ 
= (m₁ + m₂) v_{y}
v_{y} = m₁ / (m₁ + m₂) v_{oy}
v_{y} = 1/4 60
v_{y} = -15 m / s
Vertical speed is down
Answer:
The density of the mercury is 13.2 g/cm³
Explanation:
Density is a measurement that compares the amount of matter an object
has to its volume
Density is equal to mass divided by volume
We need to find the density of mercury if 500 cm³ has a mass of
6.60 kg in g/cm
We must to change The kilogram to grams
The mass of mercury is 6.60 kilograms
1 kilogram = 1000 grams
6.60 kilograms = 6.60 × 1000 = 6600 grams
Density = mass ÷ volume
The volume of the mercury is 500 cm³
The density = 6600 ÷ 500
The density = 13.2 g/cm³
<em>The density of the mercury is 13.2 g/cm³ </em>
If the car in the opposite direction turns the signal on your vehicle, then it is only likely to give way and let him or her turn before you make your turn because he or she is in the right of way and by doing this, it will prevent any complication from happening and to be able to show respect and politeness in driving.
