A33.8-lb aluminum bar, initially at 200 degree f, is placed in a tank together with 249 lb of liquid water, initially at 70 degree f, and allowed to achieve thermal equilibrium. the aluminum bar and water can be modeled as incompressible with specific heats 0.216 btu/lb*degree rankine and 0.998 btu/lb*degree rankine, respectively. for the aluminum bar and water as the system, determine:
(a) the final temperature, in degree f
(b) the amount of entropy produced within the tank, in btu/degree rankine.
note: ignore heat transfer between system and its surroundings

( (a) 533.7 r, (b) 0.1789 btu/r )

Amass of m 1.5 kg of steam is contained in a closed rigid container. initially the pressure and temperature of the steam are: p 1.5 mpa and t 240°c (superheated state), respectively. then the temperature drops to t2= 100°c as the result of heat transfer to the surroundings. determine: a) quality of the steam at the end of the process, b) heat transfer with the surroundings. for: p1.5 mpa and t 240°c: enthalpy of superheated vapour is 2900 kj/kg, specific volume of superheated vapour is 0. 1483 m/kg, while for t 100°c: enthalpy of saturated liquid water is 419kj/kg, specific volume of saturated liquid water is 0.001043m/kg, enthalpy of saturated vapour is 2676 kj/kg, specific volume of saturated vapour is 1.672 m/kg and pressure is 0.1 mpa.

Heat is added to a piston-cylinder device filled with 2 kg of air to raise its temperature 400 c from an initial temperature of t1 27 cand pressure of pi 1 mpa. the process is isobaric process. find a)-the final pressure p2 b)-the heat transfer to the air.

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