Lac is a natural resin produced by tiny lac insects (Kerria lacca), found on specific trees mostly in India, Southeast Asia, and Africa. This resin is collected from tree branches where the insects deposit it, subsequently hardening into lac.
Economic Significance of Lac:
1. Industrial Applications: Lac is integral to the manufacture of diverse products like varnishes, paints, and lacquers. It serves as a primary ingredient in shellac production, utilized as a finish and adhesive in various industries.
2.Textile Industry: Lac is employed for dyeing and finishing in the textile sector.
3. Cultural and Religious Uses: With substantial cultural value, lac is crafted into jewelry, beads, and traditional ornaments, especially in India and some regions of Southeast Asia.
4. Medicinal Purposes: In certain cultures, lac is used in folk medicine to address various health issues.
5. Export Value: Lac represents a vital export commodity for nations like India, contributing significantly to their export revenues.
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An alternating voltage is given by \( e = 8 \sin(628.4 t) \).
Find:
(i) Peak value of e.m.f.
(ii) Frequency of e.m.f.
(iii) Instantaneous value of e.m.f. at time \( t = 10 \, {ms} \)