Electrical Engineering Answers

What is Direct Memory Access? Explain the working of DMA. What are the different kinds of DMA transfers?

Convert the following arithmetic expressions from infix to reverse Polish notation.

a. A * B + C * D + E * F

b. A * B + A * (B * D + C * E)

c. A + B * [C *D + E *(F + G)]

d. (A + B) * [C * (D + E) + F]     

1)   An instruction is stored at location 300 with its address field at location 301.

          The address field has the value 400. A processor register R 1 contains the

           number 200. Evaluate the effective address if the addressing mode of the

            instruction is (a) direct; (b) immediate; (c) relative; (d) register indirect;

                   (e) index with R1 as the index register.  

. A 120Vrms 60Hz source supplies four loads connected in parallel as shown below Load 1: 150 kVA, at 0.8 pf leading Load 2: 100 kVA, at unity pf Load 3: 200 kVA, at 0.6pf lagging Load 4: 80kW and 95kVAR (inductive) Find a) Power Factor b) Calculate the value of capacitance/inductance connected in parallel that will raise the power factor to unity

Using mathematical induction prove

1+4+7+10+…+(3n-2)=n(3n-1)/n

qUESTION: When will there be a drawback in using a Virtual Memory and why?

Verify that the boundary conditions for the electric and magnetic fields at the interface between two dielectric media lead to the Fresnel equations for the reflection coefficient for both the TE and TM modes.

Convert the following numerical arithmetic expression into Reverse Polish

notation and show the stack operations for evaluating the numerical result.

(2 + 6)[7(3 + 5) + 1]

An instruction is stored at location 200 with its address field at location 201 . The

address field has the value 300. A processor register R1 contains the number 100.

Evaluate the effective address if the addressing mode of the instruction is (a) direct;

(b) immediate; (c) relative; (d) register indirect; Also explain with necessary diagram.

Convert the following arithmetic expressions from infix to Reverse Polish

notation. Also show positions in Stack by possible diagram.

a. P * Q + R* S + T* U

b. A * B + A * (B * D + C * E)

c. M + N * [O * P + Q * (R + S)]