A4 cm diameter sphere of copper is initially at a temperature of 95 °c. it is placed in a very large water bath at time t- 0. the water bath is initially at a uniform temperature of 25 °c. the heat transfer coefficient is estimated to be 400 watts / (m2 °c). the specific heat of copper is 0.385 joule (gram °c) and its density is approximately 9 gram per cc. estimate the time at which the average temperature of the sphere will be 35 °c.

Two flowing streams of argon gas are adiabatically mixed to form a single flow/stream. one stream is 1.5 kg/s at 400 kpa and 200 c while the second stream is 2kg/s at 500 kpa and 100 ? . it is stated that the exit state of the mixed single flow of argon gas is 150 c and 300 kpa. assuming there is no work output or input during the mixing process, does this process violate either the first or the second law or both? explain and state all your assumptions.

What difference(s) did you notice using a pneumatic circuit over hydraulic circuit. explain why the pneumatic piston stumbles when it hits an obstacle.

Determine whether or not it is possible to compress air adiabatically from k to 140 kpa and 400 k. what is the entropy change during this process?