2. The pressure in the steam boiler is p_(abs)=1.6 bara at barometric pressure B_(1)=720 mm Hg What will be the gauge pressure in the boiler if the barometer reading rises to B_(2)=785 mm Hg and the state of steam in the boiler remains the same?

To find the gauge pressure in the boiler when the barometer reading rises to $B_{2}=785$ mm Hg, we can use the formula:<br /><br />Gauge Pressure = Absolute Pressure - Atmospheric Pressure<br /><br />Given:<br />- Absolute Pressure, $p_{abs} = 1.6$ bara<br />- Barometric Pressure, $B_{1} = 720$ mm Hg<br />- Barometric Pressure, $B_{2} = 785$ mm Hg<br /><br />First, we need to convert the absolute pressure from bara to mm Hg:<br />$1$ bara = $750.06$ mm Hg<br />$p_{abs} = 1.6 \times 750.06 = 1200.096$ mm Hg<br /><br />Next, we can calculate the gauge pressure using the formula:<br />Gauge Pressure = $p_{abs} - B_{2}$<br />Gauge Pressure = $1200.096 - 785 = 415.096$ mm Hg<br /><br />Therefore, the gauge pressure in the boiler when the barometer reading rises to $B_{2}=785$ mm Hg and the state of steam in the boiler remains the same is approximately $415.096$ mm Hg.