A football was inflated to a gauge pressure of $$1$$ bar when the ambient temperature was $${15^ \circ }C$$. When the game started next day, the air temperature at the stadium was $${5^ \circ }C$$.
Assume that the volume of the football remains constant at $$2500c{m^3}$$

Gauge pressure of air to which the ball must have been originally inflated so that it would equal $$1$$ bar gauge at the stadium is

A football was inflated to a gauge pressure of $$1$$ bar when the ambient temperature was $${15^ \circ }C$$. When the game started next day, the air temperature at the stadium was $${5^ \circ }C$$.
Assume that the volume of the football remains constant at $$2500c{m^3}$$

The amount of heat lost by the air in the football and the gauge pressure of air in the football at the stadium respectively equal

Given below is an extract from steam tables.

Specific enthalpy of water in $$kJ/kg$$ at $$150$$ bar and $$ {45^ \circ }C$$ is

A horizontal shaft centrifugal pump lifts ware at 65°C. The suction nozzle is one meter below pump centerline. The pressure at this point equal $$200$$ $$kPa$$ gauge and velocity is $$3$$ $$m/s.$$ Steam tables show saturation pressure at $${65^0}C$$ is $$25$$ $$kPa,$$ and specific volume of the saturated liquid is $$0.001020$$$ $${m^3}/kg.$$ . The pump Net Positive suction Head ($$NPSH$$) in meters is