Answer:
1.9 MPa
Explanation:
Mass of person = 81 kg
Mass of chair = 3.8 kg
Diameter of contact point = 1.2 cm = D
Radius of contact point = 1.2/2 = 0.6 cm
Total mass of chair and person = 81 + 3.8 = 84.8 kg = M
Acceleration due to gravity = 9.81 m/s²
Force acting on the floor
F = Mg
⇒F = 84.8×9.81
⇒F = 831.888 N
Area of the contact point
A = πR²
⇒A = π0.006²
⇒A = π0.000036 m²
Area of the four points is
4A = 0.000144π m²
Pressure
[tex]p=\frac{F}{A}\\\Rightarrow p=\frac{831.888}{0.000144\pi}\\\Rightarrow p=1838876.21\ Pa=1.83887621\times 10^6\ Pa=1.9 MPa[/tex]
Pressure exerted on the floor by each leg of the chair is 1.9 MPa
