For the following questions answer them individually
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 2500 $$cm^{3}$$. 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 _____
The engine oil at $$150^\circ$$ C is cooled to $$80^\circ$$C in a parallel flow heat exchanger by water entering at $$25^\circ$$C and leaving at $$60^\circ$$ C. The exchanger effectiveness will be
The valves mounted on the boilers which change the direction of flow of steam by $$90^\circ$$ and valves fitted in the pipelines which allow the steam in the same direction are respectively called as _____
Which of the following are boiler mountings and not boiler accessories ?
A: Pressure gauge
B: Air preheater
C: Superheater
In vapour absorption refrigeration systems, which of the following fluids are commonly used?
