c
Length of the pendulum, \(l=1.5 m\)

Mass of the bob \(=m\)

Energy dissipated \(=5 \%\)

According to the law of conservation of energy, the total energy of the system remains constant.

At the horizontal position:

Potential energy of the bob, \(E_{ P }=m g l\)

Kinetic energy of the bob, \(E_{ K }=0\)

Total energy \(=m g l\)

At the lowermost point (mean position):

Potential energy of the bob, \(Ep =0\)

\(E_{ x }=\frac{1}{2} m v^{2}\)

Kinetic energy of the bob,

Total energy \(E_{x}=\frac{1}{2} m v^{2}\)

As the bob moves from the horizontal position to the lowermost point, \(5 \%\) of its energy gets dissipated.

The total energy at the lowermost point is equal to \(95 \%\) of the total energy at the horizontal point, i.e.,

\(\frac{1}{2} m v^{2}=\frac{95}{100} \times m g l\)

\(\therefore v=\sqrt{\frac{2 \times 95 \times 1.5 \times 9.8}{100}}\)

\(=5.28\; m/s\)