Answer:
a) 280MPa
b) -100MPa
c) -0.35
d) 380 MPa
Explanation:
GIVEN DATA:
mean stress 
stress amplitude 
a) 
--------------1

-----------2
solving 1 and 2 equation we get

b) 
c)
stress ratio

d)magnitude of stress range

= 280 -(-100) = 380 MPa
Answer:
No.
Explanation:
The Coefficient of Performance of the reversible heat pump is determined by the Carnot's cycle:



The power required to make the heat pump working is:


The heat absorbed from the exterior air is:


According to the Second Law of Thermodynamics, the entropy generation rate in a reversible cycle must be zero. The formula for the heat pump is:




Which contradicts the reversibility criterion according to the Second Law of Thermodynamics.
Answer:
The correct answer is "
".
Explanation:
Given:
Maximum load,
P = 50,000 N
Crack length,
a = 3mm
or,
= 3×10⁻³ m
Diameter,
d = 32 mm
As we know,
⇒ Maximum stress, 


Now,
⇒ Fracture tougness, 
On substituting the values, we get


Answer:

Explanation:
m = Mass of satellite = 15000 kg
h = Distance above Earth = 800 km
R = Radius of Earth = 6371 km
M = Mass of Earth = 
G = Gravitational constant = 
Potential energy is given by

The potential energy of the satellite is
.