NIMCET 2027 Computer Previous Year Questions (PYQs) – Page 3 of 23

✅ Concept:

To fetch data from secondary memory, certain registers are used to handle the addresses and manage the data flow between secondary memory and the CPU.

✅ Explanation of Options:

• Program Counter (PC): The Program Counter holds the address of the next instruction to execute, not used for fetching data from secondary memory.
• Memory Address Register (MAR): This is the correct answer! The MAR holds the address in memory from which data will be fetched or written, including from secondary storage. It is responsible for managing the memory access.
• Memory Buffer Register (MBR): The MBR temporarily holds data being transferred to or from memory but does not directly fetch data from secondary memory.
• Accumulator: The Accumulator holds intermediate results of arithmetic or logical operations, not used for fetching data from secondary memory.

✅ Final Answer:

The register used to fetch data from secondary memory is the $\boxed{\text{Memory Address Register (MAR)}}$.

First apply De-Morgan’s Law: $\overline{(A + B)\cdot C} = \overline{(A + B)} + \overline{C}$ 

Again apply De-Morgan’s Law on 

$\overline{(A + B)}$= $ \overline{A}\cdot \overline{B}$ 

So, $X = (\overline{A}\cdot \overline{B}) + \overline{C}$
This matches option (2):
$\overline{A\cdot B} + \overline{B\cdot C}$

✅ Concept:

Binary multiplication is done similarly to decimal multiplication, where each bit is multiplied individually. Let's break down \( 00_2 \times 11_2 \) step by step.

✅ Step 1: Understanding Binary Multiplication

We multiply each digit in the first binary number by each digit in the second binary number. The multiplication follows the same rules as decimal multiplication but with only 0's and 1's.

✅ Step 2: Perform the Multiplication

Let's multiply the two binary numbers:

• First step: \( 0 \times 1 = 0 \)
• Second step: \( 0 \times 1 = 0 \)
• Third step: \( 0 \times 1 = 0 \)

✅ Step 3: Adding the Results

Since all the results are 0, the final multiplication result is also 0.

✅ Final Answer:

The result of \( 00_2 \times 11_2 \) is: 0

$\text{For n} =10000=10^4$ 

$$Time = \frac{\text{No of tasks}}{\text{Speed  of  computer}}$$ 

$$Time = \frac{2n^2}{10^6}$$ 

$$= \frac{2\times (10^4)^2}{10^6}$$

$$= \frac{2\times 10^8}{10^6}$$

$$=2 \times 10^2$$ 

$$= 200sec$$

Programmed I/O: In program-controlled I/O, the processor program controls the complete data transfer. So only when an I/O transfer instruction is executed, the transfer could take place. It is required to check that device is ready/not for the data transfer in most cases.  Usually, the transfer is to & from a CPU register & peripheral. Here, CPU constantly monitors the peripheral. Here, until the I/O unit indicates that it is ready for transfer, the CPU wait & stays in a loop. It is time-consuming as it keeps the CPU busy needlessly.