Answer:
1. It won't break
2. 0.5 squared meters
Step-by-step explanation:
1. Pressure (P) is force (F) exerted over an area(A). Greater the force or smaller the area, the pressure will be greater. This is presented by an equation:
P = F / A
This metallic object can be placed on the table in 3 different positions, depending on which its side is pressed against the table. Since its dimensions are 3 • 6 • 8 m, surface areas of these sides are:
A1 = 3 • 6 = 18m^2
A2 = 3 • 8 = 24m^2
A3 = 6 • 8 = 48m^2
It is already stated that the smaller are, greater the pressure, so this object will exert the greatest pressure if it's placed on the table with its 18m^2 side. In this case, pressure will be:
P = 400N / 18m^2
P = 22.2 N/m^2 (N/m^2 is the same unit as Pascal)
So, the table can withstand 250 Pa of pressure, the object exerts only 22.2 Pa, which means that the glass table won't break.
2. Again, we need to know the equation that connects the force and the pressure, and that is:
P = F / A
In this case, we have both the force and the pressure, and we want to find the surface of the area. From the previous equation, area can be found as:
A = F / P
A = 20N / 40Pa (N/m^2)
A = 0.5 m^2
So, the answer is: this pressure is exerted on the area of half of squared metar.