Answer:
Correct option is C)
B is the mean position ,'C' displace position.The amplitude 'A'.
From fig(2) A = CD, OC=l
If mass of the pendulum has a velocity 'v'(linear)then centrifugal force and component 'mgcosθ' will balance the tension of string
T=mgcosθ+
l
mv
2
Now T will be max when cosθ=1
′
T
max
=mg+
l
mv
2
(it is the mean position ascosθ = 1 mean θ=0
If 'as' is angular frequency
ω=ω=
g/l
and v is equal to 'ω(a
2
−x
2
)
2
1
'. 'x' displacement of particle.
So, at mean position
v=ωa
⇒v=a
g/l
⇒v
2
=
l
a
2
g
T
max
=mg+
l
2
mga
2
=mg(1+(
l
a
)
2
)