2. A 10 g bullet has a horizontal velocity of 400 m's when it strikes and loges in a 2.5 kg
wooden block. The block is initially at rest, the mass of the bumper B can be neglected.
and he floor is smooth. In the motion after the impact, the maximum compression in the
spring is observed to be 73 mm.
Detentnine :
1. The percent of the bullet's initial kinelic energy which was lost as a result of the
collision
The velocity of die block and the bullet when the block instially impa is the
1200 NS
400 ms

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.