The spectrum of a star’s light is measured and the wavelength of one of the lines as the sodium’s line is found to be 589nm. The same line has the wavelength of 497nm when observed in the laboratory. This means the star is:

(A) Moving away from the earth
(B) moving towards the earth
(C) stationary
(D) revolving around the planet

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  • The core of transformer is laminated so that:

    (A) The core of transformer is laminated so that:
    A) The ratio of the voltage in the secondary to that in the primary may be increased
    (B) Energy losses due to eddy currents may be minimized
    (C) The weight of the transformer may be reduced
    (D) Rusting of the core may be prevented

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