Indian Institue of Management 2000 M.B.A CAT - Question Paper

info magnetically. In place of conducting wires, a magnetic processor would have rows of magnetic dots, every of which could
be polarised in 1 of 2 directions. Individual bits of info would travel down the rows as magnetic pulses, changing the
orientation of the dots as they went. Dr. Cowburn and Dr. Welland have demonstrated how a logic gate (the basic element of a
microprocessor) could work in such a scheme. In their experiment, they fed a signal in at 1 end of the chain of dots and used a
second signal to control whether it propagated along the chain.
It is, admittedly, a long way from a single logic gate to a full microprocessor, but this was actual also when the transistor was first
invented. Dr. Cowburn, who is now searching for backers to help commercialise the technology, says he believes it will be at lowest ten
years before the 1st magnetic microprocessor is constructed. But other researchers in the field agree that such a chip is the next
logical step. Dr. Prinz says that once magnetic memory is sorted out "the target is to go after the logic circuits." Whether all-magnetic
computers will ever be able to compete with other contenders that are jostling to knock electronics off its perch-such as optical,
biological and quantum computing-remains to be seen. Dr. Cowburn suggests that the future lies with hybrid machines that use
various technologies. But computing with magnetism evidently has an attraction all its own.



17. In developing magnetic memory chips to change the electronic ones, 2 option research paths are being pursued. These
are approaches based on
(1) volatile and non-volatile memories.
(2) magneto-resistance and magnetic tunnel-junctions.
(3) radiation-disruption and radiation-neutral effects.
(4) orientation of magnetised spots on the surface of a spinning disk and alignment of magnetic dots on the surface of a
conventional memory chip.


18. A binary digit or bit is represented in the magneto-resistance based magnetic chip using
(1) a layer of aluminium oxide. (2) a capacitor.
(3) a vertical pillar of magnetised material. (4) a matrix of wires.


19. In the magnetic tunnel-junctions (MTJs) tunnelling is easier when
(1) 2 magnetic layers are polarised in the identical direction.
(2) 2 magnetic layers are polarised in the opposite directions.

Earning:   Approval pending.