One of the requirements for tennis balls to be used in official competition is that, when dropped onto a rigid surface from a height of 120 in., the height of the first bounce of the ball must be in the range 55 in. <= h <= 60 in. Determine the range of the coefficients of restitution of the tennis balls satisfying this requirement. Any ideas on this?

Draw the engineering stress-strain curve for (a) bcc; (b) fcc metals and mark important points.

Select any two (2) areas of applications of chain-drive. (clo4) a)-permanent lubrication necessary b)-hydraulic forklift truck operation c)-rigging and heavy moving materials d)-relatively high maintenance costs e)-costlier than belt drives

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.