Two long copper rods of diameter d 10 mm are soldered together end to end, with solder having a melting point of 650 c. the rods are in air at 25 c with a convection coefficient of 10 w/m2 k. what is the minimum power input needed to effect the soldering?

The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

What difference(s) did you notice using a pneumatic circuit over hydraulic circuit.explain why the pneumatic piston stumbles when it hits an obstacle.

Ahe-xe mixture containing a 0.75 mole fraction of helium is used for cooling electronics in an avionics application. at a temperature of 300 k and atmospheric pressure, calculate the mass fraction of helium and the mass density, molar concentration and molecular weight of the mixture. if the cooling capacity is 10 l, what is the mass of the coolant?