Answer:
50%
Explanation:
<u>Given information</u>
Cooling load=50 kW
COP=2
Consumption=50 kW
<u>Calculations</u>
Revised input is given by cooling load/COP=50/2=25 kW
Efficiency= Work output/ Revised input=25/50=0.5
Efficiency=0.5*100=50%
Answer:
Maximum shear stress is;
τ_max = 1427.12 psi
Explanation:
We are given;
Power = 2 HP = 2 × 746 Watts = 1492 W
Angular speed;ω = 450 rev/min = 450 × 2π/60 rad/s = 47.124 rad/s
Diameter;d = 1 in
We know that; power = shear stress × angular speed
So,
P = τω
τ = P/ω
τ = 1492/47.124
τ = 31.66 N.m
Converting this to lb.in, we have;
τ = 280.2146 lb.in
Maximum shear stress is given by the formula;
τ_max = (τ•d/2)/J
J is polar moment of inertia given by the formula; J = πd⁴/32
So,
τ_max = (τ•d/2)/(πd⁴/32)
This reduces to;
τ_max = (16τ)/(πd³)
Plugging in values;
τ_max = (16 × 280.2146)/((π×1³)
τ_max = 1427.12 psi
Answer:
False
Explanation:
In electric heater electric energy is converted into heat energy. In heater wires are present which have resistance and current is flow in heater when we connect the heater to supply.
And we know that whenever current is flow in any resistance then heat is produced so in electric heaters electric energy is converted into heat energy
So this is a false statement
Answer:
The minimum volume requirement for the granite stones is 1543.64 cm³
Explanation:
1 granite stone weighs 10 denarium
100 granted stones will weigh 1000 denarium
1 denarium = 3.396g
1000 denarium = 3396g.
But we're told that 20% of material is lost during the making of these stones.
This means the mass calculated represents 80% of the original mass requirement, m.
80% of m = 3396
m = 3396/0.8 = 4425 g
This mass represents the minimum mass requirement for making the stones.
To now obtain the corresponding minimum volume requirement
Density = mass/volume
Volume = mass/density = 4425/2.75 = 1543.64 cm³
Hope this helps!!!
Answer:
The energy, that is dissipated in the resistor during this time interval is 153.6 mJ
Explanation:
Given;
number of turns, N = 179
radius of the circular coil, r = 3.95 cm = 0.0395 m
resistance, R = 10.1 Ω
time, t = 0.163 s
magnetic field strength, B = 0.573 T
Induced emf is given as;

where;
ΔФ is change in magnetic flux
ΔФ = BA = B x πr²
ΔФ = 0.573 x π(0.0395)² = 0.002809 T.m²

According to ohm's law;
V = IR
I = V / R
I = 3.0848 / 10.1
I = 0.3054 A
Energy = I²Rt
Energy = (0.3054)² x 10.1 x 0.163
Energy = 0.1536 J
Energy = 153.6 mJ
Therefore, the energy, that is dissipated in the resistor during this time interval is 153.6 mJ