Answer:
359.046 Ib
Explanation:
density = m / v ---- ( 1 )
m = mass
v = volume = l * b * h
Given data :
density = 30 Ib / ft^3
l = 2 inches = 0.1667 ft
b = 8 inches = 0.6667 ft
h = 11 ft
v ( volume ) = 0.1667 * 0.6667 * 11 = 1.22 ft^3
back to equation 1
m = 30 * 1.22 = 36.6 Ib
Actual weight ( F ) = m * g
= 36.6 * 9.81 = 359.046 Ib.
