The question asks about the primary function of a safety fuse. To answer this, we need to understand what a fuse is and how it operates within an electrical circuit.
Correct Option: B) To protect electrical circuits by breaking the circuit in case of overcurrent
This option accurately describes the primary function of a safety fuse. When an overcurrent occurs, the fuse wire heats up and melts due to the Joule heating effect (\[H = I^2 R t\]), thereby opening the circuit and stopping the flow of electricity, protecting the connected components.
The question asks about the function of a safety fuse when it experiences excessive current. This involves understanding the basic principle of how a fuse works to protect electrical circuits.
A) It heats up and melts, breaking the circuit. This accurately describes the operational principle of a safety fuse. Excessive current leads to increased heat generation (Joule heating), causing the fuse wire to melt and interrupt the circuit, thereby protecting other components.
The question asks about the material commonly used for the fusible link in a safety fuse. A safety fuse is a protective device that melts and breaks an electrical circuit when the current exceeds a safe level. The material chosen for the fusible link must have specific properties to perform this function effectively.
Correct Option: B) Lead alloy is commonly used for the fusible link in a safety fuse because of its low melting point and suitable resistivity, which allows it to melt quickly and break the circuit during an overcurrent condition.
The question asks about the unit in which the current rating of a fuse is typically measured. To answer this, we need to recall the fundamental electrical units and their applications, specifically focusing on what a fuse does and how its capacity is quantified.
C) Amperes is the correct unit for measuring the current rating of a fuse because a fuse's function is to protect against excessive electrical current, and Ampere is the standard unit for current.
The question asks for the meaning of the term "blow" in the context of electrical fuses. Understanding the function of a fuse is key to answering this question.
B) A sudden disruption of the circuit. When a fuse "blows", its internal filament melts and breaks, creating an open circuit. This immediately stops the flow of current, thus disrupting the circuit to protect it from damage due to excessive current.
The question asks to identify the type of fuse commonly used in automotive applications. We need to consider the characteristics and typical uses of each fuse type listed in the options.
B) Blade fuse is the most common type of fuse used in automotive applications. They are easily recognizable by their plastic body and two metal prongs, and they are color-coded to indicate their amperage rating.