2. (Problem 4.60 on main book, diameters different) Water flows steadily through a fire hose and nozzle. The hose is 35 mm diameter and the nozzle tip is 25 mm diameter; water gage pressure in the hose is 510 kPa, and the stream leaving the nozzle is uniform. The exit speed and pressure are 32 m/s and atmospheric, respectively. Find the force transmitted by the coupling between the nozzle and hose. Indicate whether the coupling is in tension or compression.

Answer:

coupling is in tension

Force = -244.81 N

Explanation:

Diameter of Hose ( D1 ) = 35 mm

Diameter of nozzle ( D2 ) = 25 mm

water gage pressure in hose = 510 kPa

stream leaving the nozzle is uniform

exit speed and pressure = 32 m/s and atmospheric

Determine the force transmitted by the coupling between the nozzle and hose

attached below is the remaining part of the  detailed solution

Inlet velocity ( V1 ) = V2 ( D2/D1 )^2  

= 32 ( 25 / 35 )^2

= 16.33 m/s

Combinations of velocity and acceleration

Fig_Q5
6. A steel rod is stressed by a tension force of 250 N. It is found that the rod has length of 45
m and diameter of 1.5 mm. If the modulus of elasticity of the steel rod is assumed as 2 x 105
MPa, determine the strain of the steel rod due to the applied force.