Derive the equation for time constant τ in step (c) above. Hint: Substitute each of the two data points [t1, Vo(t1)] and [t1, Vo(t2)] into the envelope function Env (t)= Vo ([infinity] ) + [ A - Vo ([infinity] )] e–t/τ to form two equations. Divide one equation by the other (side by side), simplify, take the natural log of the result, and solve for τ. Note that Env (t1) = Vo(t1) and Env (t2) = Vo(t2).

Aflywheel accelerates for 5 seconds at 2 rad/s2 from a speed of 20 rpm. determine the total number of revolutions of the flywheel during the period of its acceleration. a.5.65 b.8.43 c. 723 d.6.86

Athin walled concentric tube exchanger is used to cool engine oil from 160°c to 60°c with water that is available at 25°c acting as a coolant. the oil and water flow rates are each at 2 kg/s, and the diameter of the inner tube is 0.5 m and the corresponding value of the overall heat transfer coefficient is 250 w/m2. oc. how long must the heat exchanger be to accomplish the desired cooling? cpwater=4.187 kj/kg-candcpengine el=2.035 kj/kg·°c, oil . 120]

Air is compressed isentropically from an initial state of 300 k and 101 kpa to a final temperature of 1000 k. determine the final pressure using the following approaches: (a) approximate analysis (using properties at the average temperature) (b) exact analysis