N the melt atomization process to make fine metal powders, there usually is a variation in powder size because not all atomized droplets are of the same size. In an experiment, it was found that titanium droplets of 10 μm dia reached their solidification temperature (1660 C) in 2 milliseconds when the surrounding gas temperature was 1100 C and the initial droplet temperature was 1860 C. How long would it take for droplets of 5 μm, 20 μm, 30 μm and 50 μm diameter to cool by the same amount if they all had the same initial temperature? Given: density of Ti = 4510 kg. m-3.

Two manned satellites approaching one another at a relative speed of 0.550 m/s intend to dock. the first has a mass of 2.50 ✕ 103 kg, and the second a mass of 7.50 ✕ 103 kg. assume that the positive direction is directed from the second satellite towards the first satellite. (a) calculate the final velocity after docking, in the frame of reference in which the first satellite was originally at rest.(b) what is the loss of kinetic energy in this inelastic collision? (c) repeat both parts, in the frame of reference in which the second satellite was originally at rest. final velocity(d) loss of kinetic energy = ?

Efficiency is the ratio of to for a system a)power in to power in b)power in to power out c) power out to power out d) power out to power in

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?