Explain in your own words why light is trapped in an optical fiber. Describe at least two cases where you have observed the effects of light refraction besides the case of a swimming pool. Use examples from your own life. Why the fabrication of optical fiber is a very delicate process? What do you understand is the "Dispersion" effect in communication fibers.

Alternating current machines

Provide answers for the following: a) What is the protection offered by IP5X against solid object? (1 mark) b) What is the protection offered by IP5X against liquids? (1 mark).

Try to reconstruct the original from PWM and PPM signal directly with low pass filters. Could the signal be recovered? Why?

1. Identify FM Broadcasting System in wireless communication and design circuit.
2. Draw the appropriate circuit diagram or functioning diagram.
3. Develop circuit diagram in MATLAB for FM Broadcasting System and run the simulation.

Would it be possible to set a PID controller up on a PLC, and adjust it’s setpoint / AUTO / MANUAL selection from a SCADA system?

When trying to implement PID control, it is said that we typically find three types of processes, namely:

a) Resistance Type Processes

b) Capacitance Type Processes,

c) Inertia Type Processes. In most instances, Inertia processes are quite uncommon. Carefully consider your experience over the years, and describe an application, which according to your understanding of the subject matter, comprises of both Resistance and Capacitance effects.

Calculate the half-lifetime t1/2 of a 20 kilogram radioactive material if on the 50th year, its amount becomes 15 kilogram. Sketch the instantaneous amount of material up to infinity. using a differential equation.

Compare the Electrical and Electronics Engineering pathway,discuss about the pros and cons of the pathway.Finally choose which pathway is ideal for a future demanding industry.

Subjects:

Microelectronic
Very Large Scale Integration, Digital System Design and Implementation, Embedded Systems

Communication
Wireless and RF Communication System Design, Optical Communication System Design, Computer Networking and Security

Power
High Voltage Engineering, Industrial Instrumentation and Modern Control Systems, Power System Analysis

A silicon sample is doped with 4.5 × 10¹⁷ cm^-3 boron atoms. Assume T= 300 K, n_i = 1.5 x 10¹⁰ cm^-3

^{What is the hole concentration and electron concentration?}

Draw an equivalent circuit and list the sequence of steps to connect jumper cables properly between two car batteries when trying to jump-start a car with a run-down battery. Be sure to label both the positive and negative terminals on each battery and the red and black cables of the jumper. I t is recommended that the last connection you make should be between the black jumper cable and the run-down car; and instead of connecting it to the negative terminal of the battery, you should connect it to the frame of the car at a point away from the battery. What is the rationale for this advice? Does it matter in what order the connections are removed when you have started the car?

1. How does a temperature sensor based on a diode work? Please provide a qualitative description and Include a circuit.