2nd PUC Physics Series-8

71. A wire of resistance 3 Ω is cut into three pieces, which are then joined to form a triangle. The equivalent resistance between any corners of the triangle is :

72. The length of a conductor is halved. Its resistance will be :

73. In the above question, the conductance:

74. Siemen is the unit of:

75. How much electric energy is consumed by a 100 W lamp used for 6 hours everyday for 30 days?

76. Suppose H₁ is the heat generated per second in the filament of a 100 W, 250 V lamp and H₂ is the heat generated in the filament of a 200 W, 250 V lamp. Then H₁/H₂ is equal to:

Q.77 Two wires of copper are of the same length but’have different diameters. When they are connected in series across a battery, the heat generated is H₁ When connected in parallel across the same battery, the heat generated during the same time is H₂ Then :

78. Kirchhoffs first and second laws for electrical circuits are consequences of:

79. A 5 A fuse wire can with stand a maximum power of 1 W in circuit. The resistance of the fuse wire is:

80. The length and radius of an electric resistance of a certain wire are doubled simultaneously, then the: