The correct option is C 2.3 sec
H(s)=1s+2
r(t)=10u(t)
R(s)=10s
C(s)=H(s).R(s)=1s+2.10s
⇒10s(s+2)=As+Bs+2
10=A(s+2)+Bss=0,10=2A
⇒A=5
s=−2,10=−2B
⇒B=−5
∴C(s)=5s−5s+2
c(t)=5[1−e−2t]u(t)
Steady state value when t=∞ is 5 and steady state value is reached at
5[1−e−2t]=0.99×5
⇒1−e−2t=0.99
e−2t=0.1
⇒−2t=ln 0.1
⇒t=2.3 sec