Question

Two spherical bobs, one metallic and the other made of glass of the same size are allowed to free fall from the same height above the ground. Which one would reach earlier and why?

Answer 1

Conductors and Insulators

1. The materials that allow electricity to flow through it, are called conductors. e.g. Metals.
2. Whereas, the materials through which electricity does not flow, are called insulators. e.g. Glass.

Free fall and motion

1. When an object falls freely from a certain height to the surface of the earth, the motion is called free fall.
2. Free fall does not depend upon the size, shape, or mass of the object. It is due to the gravitational pull only.
3. Since both the glass and metal bob is falling freely, both will experience the same gravitational pull.

Lenz's law

1. Lenz's law states that the induced current is such that it opposes the free-falling motion of the conducting material.
2. Hence, due to the conductive nature of the metallic bob, and the earth's magnetic field, the metallic bob will experience some electromagnetic induction.

Therefore, the glass bob will reach the ground earlier, since it will only experience gravitational pull.