Answer Explanation:
the efficiency of the the engine is given by=1-
where T₂= lower temperature
T₁= Higher temperature
we have given efficiency =70%
lower temperature T₂=27°C=273+27=300K
higher temperature T₁=627°C=273+627=900K
efficiency=1-
=1-
=1-0.3333
=0.6666
=66%
66% is less than 70% so so inventor claim is wrong
Answer:
Marcus would have to take an exam administered by the national council of examiners for engineering and surveying.
Explanation:
Civil engineers design, construct, and maintain projects regarding infrastructure. A civil engineer also looks after the systems in the public and private sectors like roads, buildings, and systems for water supply and sewage treatment.
In order to pursue a career in civil engineering, Marcus aims to work for the city council as a civil engineer. Therefore, he would have to take an exam administered by the national council of examiners for engineering and surveying.
90% of traffic crashes are due to driver error.
True
Explanation:
Ohm's law is used here. V = IR, and variations. The voltage across all elements is the same in this parallel circuit. (V1 =V2 =V3)
The total supply current is the sum of the currents in each of the branches. (It = I1 +I2 +I3)
Rt = (8 V)/(8 A) = 1 Ω . . . . supply voltage divided by supply current
I3 = 8A -3A -4A = 1 A . . . . supply current not flowing through other branches
R1 = (8 V)/(3 A) = 8/3 Ω
R2 = (8 V)/(4 A) = 2 Ω
R3 = (8 V)/(I3) = (8 V)/(1 A) = 8 Ω
V1 = V2 = V3 = 8 V
Answer:
0.023 Pa*s
Explanation:
The surface area of the side of the inner cylinder is:
A = π*d*l
A = π*0.15*0.75 = 0.35 m^2
At 200 rpm the inner cylinder has a tangential speed of:
u = w * r
u = w * d/2
w = 200 rpm * 2π / 60 = 20.9 rad/s
u = 20.9 * 0.15 / 2 = 1.57 m/s
The torque is of 0.8 N*m, this means that the force is:
T = F * r
F = T / r
F = 2*T / d
For Newtoninan fluids with two plates moving respect of each other with a fluid between the viscous friction force would be:
F = μ*A*u / y
Where
μ: viscocity
y: separation between pates
A: surface area of the plates
Then:
2*T / d = μ*A*u/y
Rearranging:
μ = 2*T*y / (d*A*u)
μ = 2*0.8*0.0012 / (0.15*0.35*1.57) = 0.023 Pa*s