Introduction|Continental Drift|Evidence in Support of The Continental Drift|Rocks of Same Age Across The Oceans|Tillite|Placer Deposits|Force for Drifting|One Minute Revision

Evidences In Support Of Continental Drift

Introduction Of Continental Drift Theory

What are the evidences in support of the continental drift theory?

A current i, indicated by the crosses in figure, is established in a strip of copper of height h and width w. A uniform field of magnetic induction B is applied at right angle to the strip. (a) Calculate the drift velocity v_d of the electrons. (b) What are the magnitude and direction of the magnetic force F acting on the electrons? (c) What should the magnitude and direction of a homogeneous electric field E be in order to counterbalance the effect of mangetic field? (d) Calculate voltage V necessary between two sides of the conductor in order to creat this field E Between which sides of the conductor would this voltage have to be applied? (e) If no electric field is applied from the outside, the electrons will be pushed somewhat to one side and therefore will give rise to a uniform electric field E_H across the conductor until the forces of this electrostatic field E_H balance the magnetic forces encountered in part (b). What will be the magnitude and direction of field E_H ? Assume that n, the number of conductor electrons per unit volume is 1.1xx10^(29) m^-3, h = 0.02 m, w= 0.1 cm, i = 50 A, and B=2 T.

Assertion : Due to continental drift, when South America joined North America, North American animals were overridden by South American fauna. Reason : Due to the same continental drift, placental mammals of Australia survival because of lack of competition from any other mammal.

Post-Drift Studies|Convectional Current Theory|Mapping of The Ocean Floor C|Ocean Floor Configuration|Continental Margins|Abyssal Plains|Mid-Oceanic Ridges|Concept of Sea Floor Spreading|Plate Tectonics

Post-Drift Studies|Convectional Current Theory|Mapping of The Ocean Floor C|Ocean Floor Configuration|Continental Margins|Abyssal Plains|Mid-Oceanic Ridges|Concept of Sea Floor Spreading|Plate Tectonics