IOCL Junior Operator General Science MCQ || IOCL Junior Operator General Science Questions and Answers

The tool used for the simplest method of skinning wires is Electrician’s knife.

• An electrician’s knife is specifically designed for stripping insulation from wires and is considered one of the simplest tools for this task.
•  It allows for precise control when cutting through the insulation without damaging the wire itself.
• While other tools like thermal and mechanical wire strippers are also effective, the electrician’s knife is often favoured for its simplicity and ease of use in various situations.

The fundamental properties of insulation materials are best described by Insulation resistance and dielectric strength.

• Insulation Resistance: This property refers to the ability of an insulating material to resist the flow of electric current. High insulation resistance is crucial for preventing electrical leakage and ensuring safety in electrical systems.
• Dielectric Strength: This is the maximum electric field that an insulating material can withstand without undergoing electrical breakdown, meaning it can maintain its insulating properties under high voltage conditions.

The battery typically used for cellular phones is Lithium ion.

• Lithium-Ion Batteries: These are widely used in modern smartphones due to their high energy density, low self-discharge rate, and ability to be recharged multiple times. They are known for their efficiency and performance in portable electronic devices.

The relation of wire diameter with the current carrying capacity of a conductor is Directly proportional.

• As the wire diameter (or cross-sectional area) increases, the current carrying capacity also increases.
•  This is because a larger diameter allows more current to flow through the conductor without overheating.

The electrical property that opposes the flow of electrons is Resistance.

• Resistance is defined as the property of a conductor that hinders the flow of electric current. It is measured in ohms (Ω) and is a key factor in determining how much current will flow for a given voltage according to Ohm’s Law.

The purpose of covering provided over the electrical conductor is primarily for Protection against weather.

• Protection: Insulation serves as a barrier that protects electrical conductors from environmental factors such as moisture, heat, and physical damage, which can lead to short circuits or electrical failures.
• Safety: It also minimizes the risk of electric shock and prevents accidental contact with live wires, enhancing overall safety in electrical systems.

The electrical parameter measured by the megger is Insulation resistance.

• A megger, also known as a megohmmeter, is specifically designed to measure the insulation resistance of electrical equipment and wiring.
•  It applies a high voltage to the insulation and measures the resistance to determine its effectiveness in preventing leakage currents.

The formula used to find the conductance is (D) I / V.

• Conductance G is defined as the reciprocal of resistance and can be expressed using Ohm’s Law.

According to the relationship:

G = I/V

where I = the current through the conductor and V is the voltage across it.

To double the cross-sectional area of a conductor in SWG (Standard Wire Gauge), you need to increase the gauge size by approximately 3 gauge sizes.

In the Standard Wire Gauge (SWG) system:

• Increasing Gauge Numbers: As the gauge numbers increase from 0 to 36, the diameter and circular area of the wire decrease. Higher gauge numbers indicate thinner wire sizes.
• Doubling of Circular Area: The circular area approximately doubles for every three gauge sizes.
• E.g.  No. 10 SWG has about twice the cross-sectional area of No. 13 SWG.

Insulators are commonly referred to as Dielectrics.

• Dielectrics are materials that do not conduct electricity and are used to insulate conductive materials.
• They can store electrical energy when subjected to an electric field, making them essential in various electrical applications.