Answer:
B. 2.3mm
Explanation:
The correct answer for the given question is B. 2.3mm. Some aircraft are made are fabricated from aluminium which has plane stain fracture toughness. In the given scenario the plane stain toughness is
Ktc = 40 [ MPa 
]
When the Ktc increases the fracture will appear on the aircraft. In this case the maximum crack until the fracture failure is 2.5mm.
Answer:
True
Explanation:
Principles of plasma arc cutting, Uses a constricting nozzle to create, concentrate, and direct the high-velocity plasma. Plasma gas is always used
in plasma arc cutting When shielding gas is also used, the process is called dual flow plasma arc cutting. I hope this helps.
Answer 1:
Like most electrical mechanical devices, electric motors have mechanical bearings that eventually wear out.
The graphite brushes and commutator of older DC motors can also wear out over time
Answer2:
Question two is not specific enough!!
Are we talking DC?? Because if so, then yes, nothing will happen. Assuming you are insulted by ground.
Ac is a different story, as the two would light up dangerously and etc.
-your welcome!!
Answer:
81.76 N/mm² ( MPa), 1.71233
Explanation:
Modulus of elasticity = stress / strain
stress = modulus of elastic × strain
strain = ΔL / L = 250.28 mm - 250 mm / 250 mm = 0.00112
Modulus of elasticity E = 73 GPa = 73 × 10³ MPa where 1 MPa = 1 N/mm²
E = 73 × 10³N/mm²
stress = 73 × 10³N/mm²× 0.00112 = 81.76 N/mm² ( MPa)
b) Factor of safety = maximum allowable stress / induced stress = 140 MPa / 81.76 MPa = 1.71233
