
How does the Mirror Galvanometer work?
Answer
161.1k+ views
Hint: A mirror galvanometer is a type of ammeter that uses the deflection of a light beam to detect the presence of an electric current. The light beam cast onto a scale may be regarded as a long, weightless pointer.
Complete answer:
Working of mirror Galvanometer:
A lamp is placed behind the scale, and its light travels through a hole in the instrument to illuminate the mirror of the galvanometer. When an electric current is sent via the magnet/mirror assembly, the light is reflected back onto the scale.
Mirror galvanometers were employed widely in scientific equipment until efficient, steady electronic amplifiers were developed. The most typical usage were as recording devices for seismometers and subsea cables employed for telegraphy. In current times, the name mirror galvanometer is also used for systems that move laser beams by spinning a mirror via a galvanometer set-up, frequently with a servo-like control loop. The name is commonly shortened as galvo.
This sort of galvanometer is extraordinarily sensitive and can detect extremely faint current flow, such as those that traveled from Canada to Ireland over the first intercontinental cables. As may be seen by moving the current slider backward and forward, the scale reflects the flow of the current. Clerks of the day understood that observations in one direction indicated a dot, but observations in the other way indicated a dash.
Note: The ammeter calculates the total amount of current flowing through a circuit, whereas the galvanometer displays the direction of that current. The ammeter can be used to measure both direct and alternating current, while the galvanometer is only good for measuring direct current.
Complete answer:
Working of mirror Galvanometer:
A lamp is placed behind the scale, and its light travels through a hole in the instrument to illuminate the mirror of the galvanometer. When an electric current is sent via the magnet/mirror assembly, the light is reflected back onto the scale.
Mirror galvanometers were employed widely in scientific equipment until efficient, steady electronic amplifiers were developed. The most typical usage were as recording devices for seismometers and subsea cables employed for telegraphy. In current times, the name mirror galvanometer is also used for systems that move laser beams by spinning a mirror via a galvanometer set-up, frequently with a servo-like control loop. The name is commonly shortened as galvo.
This sort of galvanometer is extraordinarily sensitive and can detect extremely faint current flow, such as those that traveled from Canada to Ireland over the first intercontinental cables. As may be seen by moving the current slider backward and forward, the scale reflects the flow of the current. Clerks of the day understood that observations in one direction indicated a dot, but observations in the other way indicated a dash.
Note: The ammeter calculates the total amount of current flowing through a circuit, whereas the galvanometer displays the direction of that current. The ammeter can be used to measure both direct and alternating current, while the galvanometer is only good for measuring direct current.
Recently Updated Pages
JEE Main 2021 July 25 Shift 1 Question Paper with Answer Key

JEE Main 2021 July 22 Shift 2 Question Paper with Answer Key

Young's Double Slit Experiment Step by Step Derivation

JEE Electricity and Magnetism Important Concepts and Tips for Exam Preparation

JEE Energetics Important Concepts and Tips for Exam Preparation

JEE Isolation, Preparation and Properties of Non-metals Important Concepts and Tips for Exam Preparation

Trending doubts
JEE Main 2025 Session 2: Application Form (Out), Exam Dates (Released), Eligibility, & More

JEE Main 2025: Derivation of Equation of Trajectory in Physics

Electric Field Due to Uniformly Charged Ring for JEE Main 2025 - Formula and Derivation

Electric field due to uniformly charged sphere class 12 physics JEE_Main

Displacement-Time Graph and Velocity-Time Graph for JEE

If a wire of resistance R is stretched to double of class 12 physics JEE_Main

Other Pages
JEE Advanced Marks vs Ranks 2025: Understanding Category-wise Qualifying Marks and Previous Year Cut-offs

JEE Advanced 2025: Dates, Registration, Syllabus, Eligibility Criteria and More

JEE Advanced Weightage 2025 Chapter-Wise for Physics, Maths and Chemistry

Formula for number of images formed by two plane mirrors class 12 physics JEE_Main

Uniform Acceleration

Degree of Dissociation and Its Formula With Solved Example for JEE
