Answer:
675 Pa.
Explanation:
F = 5+2cos(15t) kN
Area (a) = 8*10-3 m2
Now at t =4 sec
F= 5+2cos(60)
= 5+2*0.5
= 6 kN
Now ,force efficiency is 90%.
Hence,the effectively transmitted force,
Fe = 0.90*6
= 5.4 kN
Hence,pressure is given as,
P = Fe/a
= 5.4*10^3/(8
*10^-3))
P = 675 Pa....answer
