A tank, closed tightly with a lid, is completely filled with water and is rigidly fixed on a car. The car moves with a constant acceleration of 20cm*s^(-2). Determine the pressure at a point 10 cm below the lid and at a distance of 10 cm from the front wall of the tank.

A tank, closed tightly with a lid, is completely filled with water and

1.	A tank, closed tightly with a lid, is completely filled with water and is rigidly fixed on a car. The car moves with a constant acceleration of 20cm*s^(-2). Determine the pressure at a point 10 cm below the lid and at a distance of 10 cm from the front wall of the tank.
Answer» Solution :LET us consider a vertical disc of unit area KEPT at a depth H from the upper surface of the tank. The disc is at a distance x from the front wall of the car and its width is dx. Let the pressures at distances x and (x + dx) be p and (p + dp) respectively. `therefore" "p+dp-p=rhodxa` [`rho` = density of the liquid, `rhodx` = mass of the liquid DISPLACED by the disc, and a = acceleration of the car] or, `dp=arhodx` `therefore" "intdp=arhointdx` or, `p=arhox+c" "`[c = integration constant] Now, if x = 0, then p = `hrhog`. `therefore" "hrhog=c` `therefore" "p=arhox+hrhog=rho(ax+hg)` `therefore` The pressure at a point 10 cm below the lid and at a distances of 10 cm from the front wall of the tank, `p=1(20xx10+10xx980)=200+9800` `= 10000dyn*cm^(-2)`