Introduction:
The question asks whether magnetic memory devices are widely used for RAM in modern systems due to ease of erasure and reuse. Historically, magnetic core memory provided random access and non-volatility, but it has been obsolete for decades. Contemporary RAM is semiconductor-based (DRAM and SRAM), not magnetic media.
Given Data / Assumptions:
- Modern main memory uses DRAM; caches and many buffers use SRAM.
- Magnetic media today primarily serve as storage (HDDs, magnetic tape), not volatile RAM.
- "Widely used" refers to mainstream contemporary computing.
Concept / Approach:
While magnetic storage is reusable and erasable, it is not used as RAM because its access time and bandwidth are far slower and its interfaces are block-oriented rather than true random, low-latency access at the word/byte level. RAM demands nanosecond-scale access with bus-level integration, which semiconductor memories provide. Therefore, the statement is incorrect for modern systems.
Step-by-Step Solution:
Define RAM requirements: nanosecond access, random addressing, high bandwidth, direct bus attachment.Compare with magnetic devices: millisecond access for disks, streaming/block interfaces for tape.Conclude: magnetic devices are unsuitable for RAM in current architectures; semiconductor RAM dominates.
Verification / Alternative check:
Survey system block diagrams: CPUs connect to DRAM modules (e.g., DDR generations) and use SRAM caches; no magnetic RAM in mainstream usage.
Why Other Options Are Wrong:
Correct: Would imply widespread current use of magnetic RAM, which is false.True only for core memory in the 1960s: That was historical, not modern widespread practice.Depends on UV eraser availability: UV erasure is irrelevant to magnetic media and RAM.
Common Pitfalls:
Confusing secondary storage (HDDs) with main memory (RAM).Assuming "erasable" implies suitability for RAM without considering latency and interface.
Final Answer:
Incorrect
Discussion & Comments