Question

a rectangular block with side 5cm*10cm*20cm is made of materials of 32.5g per centimeter cube, find the maximum pressure that exert when resting with one of the face on a horizontal surface​

Answer 1

P = 63765 [Pa]

Step-by-step explanation:

In order to solve this problem we must use the definition of density which tells us that density is equal to the mass divided on the volume.

Now we must find the volume

`V = 5*10*20 = 1000[cm^(3)] \\in cubic meter\\1000[cm^(3)]*(1m^(3) )/(100^(3)[cm^(3) ] ) \\ V=1*10^(-3)[m^(3) ]`

Now we must use the density given:

`d =32.5[(g)/(cm^(3))]\\32.5[(g)/(cm^(3))]*(100^(3)cm^(3) )/(1^(3) m^(3) )*(1kg)/(1000g)\\ d= 32500[(kg)/(m^(3) ) ]`

Now we can calculate the mass:

m = d * V

m = 32500 * 0.001

m = 32.5 [kg]

We know that pressure is given by the following equation:

P = F/A

where:

F = Force or weigth [N] or = m*g

where:

g = gravity = 9.81[m/s^2]

A = area [m^2]

The pressure will be maximum when the area is minimum. So the mimimun area is given by 5[cm] multiply by 10 [cm]

A = 5*10 =50[cm^2] = 0.005 [m^2]

F = 32.5 * 9.81 = 319[N]

P = 319/0.005

P = 63765 [Pa]