Aao Sikhte hai

Electricity and Magnetic effect of current  1. A voltmeter has a high resistance so that it takes a negligible current from the circuit. 2. An ammeter should have very low resistance so that it may not change the value of the current flowing in the circuit. 3. According to Ohm's law , "At constant temperature, the current flowing through a conductor is directly proportional to the potential difference across its end". 4. Factors affecting the resistance of a conductor: (i) Length of the conductor (ii) Area of cross section of the conductor (iii) nature of the material of the conductor (iv) temperature of the conductor. 5.The SI unit  of resistivity is Ohm meter. 6. Advantage of parallel Circuits in Domestic wiring: (i) The overall resistance of household circuits is reduced due to which the current from the power supply is high. (ii) If one electrical appliance stops working due to some defect, then all other appliances keep working normally. (iii) Each electrical applian