The charge on the electron was found out by
The charge on the electron was found out by
The correct option is A R.A Millikan
The charge (e) on an electron was determined by R.A. Millikan in 1909 by an 'oil drop' experiment.
Millikan's oil drop method: In this method, oil droplets in the form of mist, produced by an atomizer, are allowed to enter through a tiny hole in the upper plate of an electrical condenser. The downward motion of these droplets is viewed through a telescope equipped with a micrometer eye piece. By measuring the rate of fall of these droplets, Millikan measured the mass of oil droplets. The air inside the chamber is ionized by passing a beam of X-rays through it. The electrical charge on these oil droplets is acquired because of collisions with gaseous ions. By measuring the velocity of a given oil droplet as it falls freely under the influence of gravity and then in an electric field, it is possible to calculate the charge(q) on the droplet. The fall of these charged oil droplets can be retarded, accelerated, or made stationary depending upon the charge on the droplets and the polarity and strength of the voltage applied to the plate. By carefully measuring the effects of electrical field strength on the motion of oil droplets, Millikan concluded that the magnitude of electric charge, q, on the droplets is always an integral multiple of the electric charge, e, that is, q = ne, where n = 1, 2, 3 .....
The Millikan oil drop apparatus for measuring charge 'e'. In the chamber, the forces acting on the oil drop are gravitational force, electrostatic force due to electrical field, and a viscous drag force on the moving oil drop.
R.A Millikan
The charge (e) on an electron was determined by R.A. Millikan in 1909 by an 'oil drop' experiment.
Millikan's oil drop method: In this method, oil droplets in the form of mist, produced by an atomizer, are allowed to enter through a tiny hole in the upper plate of an electrical condenser. The downward motion of these droplets is viewed through a telescope equipped with a micrometer eye piece. By measuring the rate of fall of these droplets, Millikan measured the mass of oil droplets. The air inside the chamber is ionized by passing a beam of X-rays through it. The electrical charge on these oil droplets is acquired because of collisions with gaseous ions. By measuring the velocity of a given oil droplet as it falls freely under the influence of gravity and then in an electric field, it is possible to calculate the charge(q) on the droplet. The fall of these charged oil droplets can be retarded, accelerated, or made stationary depending upon the charge on the droplets and the polarity and strength of the voltage applied to the plate. By carefully measuring the effects of electrical field strength on the motion of oil droplets, Millikan concluded that the magnitude of electric charge, q, on the droplets is always an integral multiple of the electric charge, e, that is, q = ne, where n = 1, 2, 3 .....
The Millikan oil drop apparatus for measuring charge 'e'. In the chamber, the forces acting on the oil drop are gravitational force, electrostatic force due to electrical field, and a viscous drag force on the moving oil drop.
