What are the different polymorphs of zirconia?

Air at $77^{\circ} \mathrm{F}$ flows at $M=1.9$. Determine the air speed and the Mach angle.

A 5 -by-5-cm plate is maintained at $50^{\circ} \mathrm{C}$ and inclined at $60^{\circ}$ with the horizontal. Determine the heat loss from both sides of the plate to water at $20^{\circ} \mathrm{C}$.

Find the volumes described by the following: (a) $2 \leq r \leq 5 ; \pi / 2 \leq \phi \leq \pi ; 0 \leq z \leq 2$ (b) $0 \leq R \leq 5 ; 0 \leq \theta \leq \pi / 3 ; 0 \leq \phi \leq 2 \pi$ Also sketch the outline of each volume.

A heat pump designer claims to have an air-source heat pump whose coefficient of performance is $1.8$ when heating a building whose interior temperature is $300 \mathrm{~K}$ and when the atmospheric air surrounding the building is at $260 \mathrm{~K}$. Is this claim valid?

Determine the force P required to maintain the 200-kg engine in the position for which

$$\begin{equation} \theta=30^{\circ} \end{equation}$$

. The diameter of the pulley at B is negligible.

Using the relation $ds\:=\:(\delta Q/T)_{\text{int rev}}$ for the definition of entropy, calculate the change in the specific entropy of R-134a as it is heated at a constant pressure of 200 kPa from a saturated liquid to a saturated vapor. Use the R-134a tables to verify your answer.

The circular access port in the side of a water standpipe has a diameter of 0.6 m and is held in place by eight bolts evenly spaced around the circumference. If the standpipe diameter is 7 m and the center of the port is located 12 m below the free surface of the water, determine (a) the total force on the port and (b) the appropriate bolt diameter.

In previous problem, what is the largest value of $\alpha$ for which the van can remain in equilibrium if it points up the slope?

The 2000-lb airplane is flying at an altitude of $5000\ \mathrm{ft}$. Each wing has a span of $16\ \mathrm{ft}$ and a cord length of $3.5 \mathrm{ft}$, and it can be classified as a NACA 2409 section. If the plane is flying at $225\ \mathrm{ft} / \mathrm{s}$, find the total drag on the wings. Also, what is the angle of attack and the corresponding velocity at which the condition of stall occurs?

The two springs are identical, with unstretched length $0.4 \mathrm{~m}$. When the $50-\mathrm{kg}$ mass is suspended at $B$, the length of each spring increases to $0.6 \mathrm{~m}$. What is the spring constant $k$ ?

The onset of turbulence in a gas flowing within a circular tube occurs at $R e_{D, c} \approx 2300$, while a transition from incompressible to compressible flow occurs at a critical Mach number of $M a_{c} \approx 0.3$. Determine the critical tube diameter $D_{c}$, below which incompressible turbulent flow and heat transfer cannot exist for (i) air, (ii) $\mathrm{CO}_{2}$, (iii) He. Evaluate properties at atmospheric pressure and a temperature of T=300 K.

A full journal bearing is 28 mm long. The shaft journal has a diameter of 56 mm with a unilateral tolerance of - 0.012 mm. The bushing bore has a diameter of 56.05 mm with a unilateral tolerance of 0.012 mm. The load is 2.4 kN and the journal speed is 900 rev/min. For the minimum clearance assembly find the minimum oil-film thickness, the power loss, and the side flow if the operating temperature is $65^{\circ} \mathrm{C}$ and SAE 40 lubricating oil is used.

What is the difference between disbenefits and costs?