What is the primary purpose of a fuse in an electrical circuit?
C
To protect against overcurrent
Analysis & Theory
Fuses protect electrical circuits by breaking the circuit when excessive current flows through it.
Which type of fuse is commonly used in mining detonations?
Analysis & Theory
Safety fuses are commonly used in mining to ignite detonators through timed burning.
What is the function of a safety fuse in blasting operations?
B
To provide delay before explosion
D
To reduce explosive power
Analysis & Theory
A safety fuse provides a timed delay before the detonation, allowing safe retreat.
Which type of fuse contains a small explosive charge and is initiated by heat or flame?
Analysis & Theory
A detonating fuse contains explosive material and transfers detonation along its length.
Which type of fuse is designed to carry a predetermined current and melt when the limit is exceeded?
Analysis & Theory
All listed fuses are types that melt when current exceeds the rated value, breaking the circuit.
What color coding is often used for safety fuses in blasting to indicate burn time?
A
Red for fast, green for slow
B
Yellow for medium, red for slow
D
Green for fast, red for slow
Analysis & Theory
Standard color codes like red (quick) and green (slow) help identify fuse burn rates.
Which of the following fuses burns with a visible flame and is waterproof?
Analysis & Theory
Safety fuses are designed to burn reliably even in damp or wet conditions.
How is a fuse rating determined?
C
By the maximum current it can safely carry
Analysis & Theory
Fuse ratings indicate the maximum current a fuse can carry without melting.
What material is commonly used inside electric fuses as the fuse element?
Analysis & Theory
Copper or zinc is used because of predictable melting behavior and good conductivity.
Which type of fuse is known for instantaneous operation and is used where fast response is needed?
Analysis & Theory
Fast-blow fuses react instantly to overcurrent, ideal for protecting sensitive electronics.