Advertisements
Advertisements
प्रश्न
A heating element is marked 210 V, 630 W. What is the value of the current drawn by the element when connected to a 210 V dc source?
उत्तर
In dc source, P = VI. Given that P = 630 W and V = 210 V. Therefore, `I = P/V = 630/210 = 3 A` .
APPEARS IN
संबंधित प्रश्न
A negligibly small current is passed through a wire of length 15 m and uniform cross-section 6.0 × 10−7 m2, and its resistance is measured to be 5.0 Ω. What is the resistivity of the material at the temperature of the experiment?
Two wires of equal length, one of aluminium and the other of copper have the same resistance. Which of the two wires is lighter? Hence explain why aluminium wires are preferred for overhead power cables.
(ρAl = 2.63 × 10−8 Ω m, ρCu = 1.72 × 10−8 Ω m, Relative density of Al = 2.7, of Cu = 8.9.)
Choose the correct alternative:
Alloys of metals usually have (greater/less) resistivity than that of their constituent metals.
A heating element is marked 210 V, 630 W. Find the resistance of the element when connected to a 210 V dc source.
Two wires of equal length, one of copper and the other of manganin have the same resistance. Which wire is thicker?
Two resistors A and B have resistances RA and RB, respectively, and RA < RB. The resistivities of their materials are ρA and ρB.
A wire of length 1 m and radius 0.1 mm has a resistance of 100 Ω. Find the resistivity of the material.
The electrochemical equivalent of a material depends on _______________ .
Choose the correct alternative:
Alloys usually have much (lower/higher) temperature coefficients of resistance than pure metals.
The resistivity of alloy manganin is ______.
