During a high reynolds number experiment, the total drag force acting on a spherical body of diameter d = 12 cm subjected to airflow at 1 atm and 5°c is measured to be 5.9 n. the pressure drag acting on the body is calculated by integrating the pressure distribution (measured by the use of pressure sensors throughout the surface) to be 4.9 n. determine the friction drag coefficient of the sphere. take the density and kinematic viscosity of air at 1 atm and 5°c as rho = 1.269 kg/m3 and v = 1.382 × 10–5 m2/s and the drag coefficient of the sphere in turbulent flow as cd = 0.2. (round the final answer to four decimal places.)

If a particle moves along a path such that r : (3 sin t) m and ? : 2t rad, where t is in seconds. what is the particle's acceleration in m/s in 4 seconds? a)- 16.43 b)- 16.29 c)- 15.21 d)- 13.79

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

During a steady flow process, the change of energy with respect to time is zero. a)- true b)- false