2 The instrument used for experimental determination of
the value of the universal gravitational constant G is
called
Galilio’s telescope
ballistic pendulum
Newton’s balance
Cavendish
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cavendish
The instrument used for experimental determination of the value of the universal gravitational constant G is called the Cavendish experiment. This experiment was first conducted by the British scientist Henry Cavendish in 1798.
Now, to understand how this experiment works, let's break it down step by step:
1. Setup: The Cavendish experiment consists of two small lead spheres (known as "test masses") suspended from a thin wire in a horizontal setup. These test masses are positioned close to two larger lead spheres (known as "attracting masses").
2. Measurement of the torsion constant: Before performing the experiment, the torsion constant of the wire is measured. This constant determines how much the wire twists given a certain amount of torque.
3. Measurement of the attractive force: The setup is shielded from external disturbances to minimize any interference. When the experiment is initiated, the gravitational attraction between the test masses and the attracting masses causes a small rotational motion of the wire, known as torsion.
4. Measurement of the torsion: A sensitive device (such as a laser or mirror) is used to measure the torsion of the wire accurately. By analyzing the oscillation period of the torsion, the force of gravitational attraction between the test masses and attracting masses can be determined.
5. Calculation of the gravitational constant: With the value of the attractive force and the masses of the objects involved, the experimental value of the universal gravitational constant G can be calculated using the equation F = G * m1 * m2 / r^2, where F is the force of gravity, m1 and m2 are the masses of the test masses and attracting masses, and r is the distance between them.
So, to answer your question, the correct instrument used for experimental determination of the value of the universal gravitational constant G is the Cavendish experiment.