Hw7.4. a copper sphere of a diameter 5 cm at 177c is cooled by an air stream at 27c, as described below. the air stream velocity is 0.5 m/s at 1 atm. calculate (a) the average rate of heat convection over the entire surface of the sphere and (b) the rate of heat convection into the air stream

Ahelical coil spring has a mean diameter of 50 mm, a wire diameter of 5.5 mm and is wound with a pitch of 10 mm. the spring steel has an ultimate strength of 1250 mpa. find the force needed to compress the spring solid and the wire stress in this condition. state whether the spring will return to its initial length.