A rectangular slab (43m x 12m x 2.5m) of slate rests on a 26 degree incline. The density of the slab is 3.2 x 10^3 kg/m^3. The coefficient of static friction between the slab & the plane is 0.36.
a) Calculate the component of the slab's weight acting parallel to the incline.
b) Calculate the static frictional force on the slab
c) From the above calculation you can see that the slab will slide down the plane. To stabilise the slab, bolts are driven perpendicular to the incline. Each bolt has a cross-sectional area of 6.4cm^2 and a breaking stress of 3.8 x 10^8 N/m^2. Use a safety factor of 2 and calculate the number of bolts needed.