exemption u/s 54GA

yes exemption u/s 54GA is allowed for an assessee being an industrial undertaking but its only for Machinery, plant, building, or land used  for the business of an industrial undertaking situated in an urban area and Transfer should be due to shifting to any Special Economic Zone whether developed in any urban area or any other area ,Within a period of 1 year before or 3 years after the date of transfer purchased machinery, plant or acquired building or land   or   constructed   building   and completed shifting to the new area.

Quantum of exemption :If the cost of the new assets and expenses incurred for shifting are greater than the capital gain, the whole of such capital gain. Otherwise capital gain to the extent of the cost of the new asset

Its should be noted that computers and cars would constitute as "plant" for the limited purpose of 54GA hence the exemption would be available for computers and cars as well , apart from other plant and machinery( first hand or second hand ) as per my knowledge there is no restriction placed on second hand machinery

in given e.g. is it also applicable to CAR , COMPUTER ??

yes , car and computer would constitute as plant