Explanation:
Inertia is the measure of the mass of an object. It is the tendency of an object to change the direction of an object.
Momentum is the product of mass and velocity. When an object having mass m moves with a particular velocity it will have momentum.
If the speed of an object is changed from u to v, its momentum can be changed and it can be calculated as :
Δp = m(v-u)
Hence, this is the required solution.
Answer:
A. Kinetic energies are equal.
Explanation:
The kinetic energy of the bodies will be equal since the mass and speed are the same.
Kinetic energy is the energy due to the motion of a body.
Mathematically;
K.E = m v²
m is the mass
v is the speed
The kinetic energy is a scalar quantity with no regard for direction.
This Question is incomplete.The complete question is
Combustion gases enter a gas turbine at 627∘C and 1.2 MPa at a rate of 2.5 kg/s and leave at 527∘C and 500 kPa. It is estimated that heat is lost from the turbine at a rate of 20 kW. Using air properties for the combustion gases and assuming the surroundings to be at 25∘C and 100 kPa, determine (a) the actual and reversible power outputs of the turbine. (b) the exergy destroyed within the turbine, and (c) the second-law efficiency of the turbine.
Answer:
(a) W=257.5kW Wrev=367.3kW
(b) X=109.8kW
(c) n=0.7
Explanation:
For Part(a)
Actual power output is determined from the energy balance. The final and initial enthalpy are taken from A-17 for the given temperature
mh₁=W+Q+mh₂
W=m(h₁-h₂)-Q
W=2.5(939.93-821.95)-20
W=257.5kW
The reversible power output is determined from the rate of energy destruction
Wrev=W+X
Wrev=W+T₀(m(s₂-s₁-Rln(p₂/p₁)+Q/T₀)
Wrev=257.5+298( 2.5 (2.71787-2.84856-0.287*ln(500/1200)+20/298)
Wrev=367.3kW
For part(b)
X=Wrev-W
X=367.3-257.5
X=109.8kW
For part (c)
Second-law efficiency is determined from the ratio of the actual and reversible power output:
n=W/Wrev
n=257.5/367.3
n=0.7
(3.6 newton-second) / (600 newton) = 0.006 second