What is a Foucault’s Pendulum, hanging in the new Parliament building

What is a Foucault’s Pendulum, hanging in the new Parliament building

Context- Suspended from the ceiling of the Central Foyer of India’s new Parliament building, inaugurated on Sunday (May 29), is a Foucault pendulum that all but touches the floor as it rotates on its axis. The pendulum hangs from a skylight at the top of the Constitution Hall, and signifies the “integration of the idea of India with the idea of the cosmos”.

Created by the National Council of Science Museum (NCSM) in Kolkata, the pendulum is being dubbed as the largest such piece in India, 22 metre in height, and weighing a staggering 36 kg.

(Credits- Hindustan Times)

On the ground, a circular installation has been created to allow the pendulum’s movement, with a short grill around it, allowing the visitors to stand around. At the latitude of the Parliament, it takes 49 hours, 59 minutes, and 18 seconds for the pendulum to complete one rotation, as per the details displayed at the installation.

What is a Foucault’s pendulum?

  • The original Foucault’s pendulum, named after 19th century French scientist Leon Foucault, is a simple experiment to demonstrate the earth’s rotation. When Foucault carried out this experiment for the public in 1851, it was the first direct visual evidence of the fact that the earth rotates on its axis.
  • The experimental set-up involves a heavy object hung from a height with a string, free to swing in any direction. Once set in to-and-fro motion, the pendulum is seen to change its orientation slowly over time.
  • For example, if the initial motion imparted to it was in the north-south direction, after a few hours it could be seen moving in the east-west direction.
  • Actually, it is not the pendulum that changes its plane of motion, but the ground beneath it. Observers standing on the ground do not notice the earth’s rotation, because they too are rotating with the earth, but can notice the change in orientation of the pendulum.

How was the pendulum made for the Parliament?

  • Tapas Moharana, Project Incharge, says that all the components of the pendulum have been completely made in India, and creating the entire piece took them around 10-12 months.
  • On the symbolism of the pendulum and its prime place in the hallowed building, Moharana said that Article 51A of the Constitution enshrines every citizen “to develop the scientific temper, humanism, and the spirit of inquiry and reform”. In keeping with that, there was a decision by those handling the project to have a piece reflecting this

Syllabus- Prelims; Current Affairs

Source- Indian Express