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Heating and Chemical Effect of Current — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsHeating and Chemical Effect of Current1 Mark
Question

Four identical electrical lamps are labelled 1.5V, 0.5A which describes the condition necessary for them to operate at normal brightness. A 12V battery of negligible internal resistance is connected to lamps as shown, then

(a) The value of R for normal brightness of each lamp is (3/4) W

(b) The value of R for normal brightness of each lamp is (21/4) W

(c) Total power dissipated in circuit when all lamps are normally bright is 24W

(d) Power dissipated in R is 21W when all lamps are normally bright
✓

Answer

(b) The value of R for normal brightness of each lamp is (21/4) W

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