Question

Explain the origin of upper yield point and lower yield point in nonferrous alloys. (hint: use
strain rate formula , where b is Burger’s vector,  is dislocation density, v− is dislocation velocity)

Answer 1

Answer:

choose the correct option

the inside of the solar cooker and the pipes of the solar water heater are printed black because black surface is a

number one good reflector of heat

2 .good absorber of heater

3 . poor absorber of heater

4 .good radiator of heater