How many bits make one nibble?
- A.2 bits
- B.4 bits
- C.8 bits
- D.16 bits
Correct answer
Explanation
The correct answer is B, 4 bits. A nibble is half a byte, that is four binary digits, and it matters because one nibble is written as exactly one hexadecimal digit, from 0 to F. That is why memory addresses in hexadecimal are read four bits at a time.
Option A, 2 bits, has no standard name in this ladder and is simply a distractor. Option C, 8 bits, is one byte, the space needed to store a single character in the ASCII scheme, and it is the most common wrong choice because candidates confuse the byte with the nibble. Option D, 16 bits, is two bytes, often called a half word on a 32-bit machine. Fix the small ladder in memory: 1 bit, 1 nibble of 4 bits, 1 byte of 8 bits, and then every higher unit multiplying by 1,024.
Read the full article: Memory and Storage: RAM, ROM, Cache and Units
Practice Questions
View allWhich of the following is the fastest memory in a computer system?
- A.Cache memory
- B.Register
- C.Main memory
- D.Hard disk
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A register is built into the CPU itself and holds the word the arithmetic and logic unit is operating on at that instant, so it is read and written in a single clock cycle.
Read the full explanation →Which type of memory has to be refreshed thousands of times per second to retain its contents?
- A.SRAM
- B.DRAM
- C.ROM
- D.Flash memory
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Dynamic RAM stores each bit as a charge on a very small capacitor, and that charge leaks away in a few milliseconds, so the memory controller has to read and rewrite every cell continuously.
Read the full explanation →The contents of an EPROM chip are erased by exposing it to
- A.An electrical signal
- B.Ultraviolet light
- C.A magnetic field
- D.Infrared radiation
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An Erasable Programmable Read Only Memory chip carries a small quartz window over the silicon; ultraviolet light shone through that window releases the trapped charge from every cell at once and returns the chip to its blank state, after which it can be programmed again.
Read the full explanation →One terabyte is equal to how many gigabytes?
- A.100 GB
- B.512 GB
- C.1,024 GB
- D.2,048 GB
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Every step in the ladder of storage units multiplies by 1,024, because 1,024 is 2 raised to the power 10 and memory is addressed in binary.
Read the full explanation →Which of the following is an example of volatile memory?
- A.ROM
- B.RAM
- C.Hard disk
- D.Pen drive
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Random Access Memory holds a bit only while it is powered, whether the cell is a flip-flop in static RAM or a leaking capacitor in dynamic RAM.
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