Bi-quartz Polarimeter

Q.What is Polarimeter? A.It is a device used to measure the angle of rotation of plane of polarisation rotated by an optically active substance. Q.What is specific rotation? A.Specific rotation of an optically active substance at a given temperature is the rotation in degrees of the plane of polarisation of incident polarized beam produced by one […]

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Diffraction Grating

Q.What is diffraction? A.The process by which a beam of light or other system of waves is spread out as a result of passing through a narrow aperture or across an edge, typically accompanied by interference between the wave forms produced. Q.What is diffraction grating? A.It is an optically flat glass plate on which large […]

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Carey Foster Bridge

It was invented by George Carey Foster Q.What is resistance? A.Resistance R=V \ I, where V is the potential difference applied across the wire and I is the current flowing through it due to the potential difference. Q.What is specific resistance? A.Specific resistance of a material is the resistance of one centimeter length of wire whose […]

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It is named after the German scientist Hermann Ludwig Ferdinand von Helmholtz. Q.What is Helmholtz Galvanometer? A. A Helmholtz galvanometer , like other galvanometers , is an instrument which can be use to measure dc current in the circuit.It is an improved form of the tangent galvanometer. . Q. On what principle is Helmholtz Galvanometer based? A. It […]