Physics
posted by Dillon on .
I am new at physics and having a very hard time. Could you please help. Thank you.
Show that the water pressure at the bottom of the 50mhigh water tower in Figure 5.3 is 490,000 N/m2, or is approximately 500 kPa.

One way:
How much does a column of water one meter square at the bottom and 50 m high weigh?
Density of water = 1000 Kg /m^3
Volume of column = 50*1 = 50 m^3
so
mass of the column = 50,000 Kg
weight = m g = 9.81 * 50,000 = 490,500 Newtons spread over one m^2 so
490,000 N/m^2
another way
pressure = rho g h
= 1000 * 9.81 * 50 = 490,500 N/m^2 again
since a Pascal is a Newton/meter^2 we have already answered the second part, about 500 * 10^3 Pascals