Lamp and Scale Arrangement for Ballistic Galvanometer (Griffith Pattern)
This instrument is designed according to the well-established Griffith Pattern, making it highly suitable for use with reflecting Ballistic Galvanometers in physics laboratories. The apparatus is housed in a robust cabinet fabricated from high-quality 20 SWG sheet metal, measuring approximately 6″ × 4″ × 3″. The top surface is fitted with an attractive printed aluminum panel, providing both durability and ease of operation.
Inside the cabinet is a heavy-duty transformer rated at 6 Volts, 3.5 Amperes, specially designed to power the lamp assembly. The lamp house is manufactured from high-grade aluminum-silver alloy and is precision machined for durability and smooth operation. It is finished with an elegant duco paint coating for enhanced appearance and protection.
The unit is equipped with a specially selected 6 Volt, 20 Watt lamp, connected to the transformer through a convenient detachable male-female plug arrangement. A rack-and-pinion focusing mechanism allows accurate adjustment of the light beam to obtain sharp and well-defined images.
For optimum illumination, the lamp house contains a high-quality double convex lens made from imported optical glass. The lens has a diameter of 18 mm and a focal length of approximately 4 cm, ensuring bright and focused light output. The lamp assembly can be moved vertically along a supporting rod and can also be tilted in the vertical plane for precise alignment.
During operation, the concentrated beam of light is directed onto the concave mirror of the Ballistic Galvanometer. The reflected beam produces a bright spot on a translucent Perspex scale mounted above the lamp house. The scale is clearly graduated from –25 cm to +25 cm and 0 to 50 cm, enabling accurate observation and measurement of galvanometer deflections.
Specifications
Application: Physics and Educational Laboratories
Material: Metal Construction
Type: Analog
Operation: Manual
Power Supply: AC Mains
Pattern: Griffith Type
Focusing Mechanism: Rack and Pinion Adjustment
Lamp Rating: 6 V, 20 W
Transformer Rating: 6 V, 3.5 A
Scale Type: Translucent Perspex Scale with Clear Graduations
The apparatus provides a bright, sharp, and stable light spot for accurate observation of galvanometer deflections, making it an essential accessory for experiments involving ballistic and reflecting galvanometers.
