A constant voltage is applied between the two ends of a uniform metallic wire, heat ‘H’ is developed in it. (iv) high temperature coefficient of resistivity and high specific resistance (iii) low temperature coefficient of resistivity and low specific resistance (ii) high temperature coefficient of resistivity and low specific resistance (i) low temperature coefficient of resistivity and high specific resistance We use alloys for making standard resistors because they have (iv) decreases for a conductor and increases for a semiconductor. (iii) increases for a conductor and decreases for a semiconductor. By increasing the temperature, the specific resistance of a conductor and a semiconductor.

If the lengths and radii of the wires are in the ratio of 3:2 and 2:3, then the ratio of the current passing through the wire will be An electric current is passed through a circuit containing two wires of same material, connected in parallel. The best instrument for accurate measurement of EMF of a cell is. After charging battery is disconnected and a dielectric slab with dielectric constant ‘K’ is inserted between its plates, the potential across the plates of a capacitor will become A capacitor plate is charged by a battery with ‘V’ volts. (iv) The electric field over the gaussian surface remains continuous and uniform at every point. (iii) Gauss theorem can be applied to non-uniform electric field. (ii) Electric flux depends upon the geometry of the gaussian surface. (i) All the charges whether inside or outside the gaussian surface contribute to the electric flux. The electrostatic force between them in vacuum at the same distance r will be. Two point charges placed in a medium of dielectric constant 5 are at a distance r between them, experiencing an electrostatic force ‘F’. Three capacitors 2♟, 3♟ and 6♟ are joined in series with each other. The amount of work done in rotating the dipole by 900 is. An electric dipole of moment p is placed parallel to the uniform electric field.

Sample paper class 9 physics cbse