What happens to resistance when length of wire is doubled?
What happens to resistance when length is doubled? From the equation, we understand that resistance is directly proportional to the length of the conductor and inversely proportional to the crossectional area of the conductor. Doubling the length doubles the resistance.
What is electrical resistivity in a series electrical circuit comprising a resistor made up of a metallic wire the ammeter reads 5 a the reading of the ammeter decreases to half when the length of the wire is doubled why?
Answer: The resistivity of a material is defined as the resistance of a conductor made of that material of unit length and unit cross-sectional area. R is doubled while V remains unchanged. Hence, current becomes half.
Why does reading of ammeter decreases to half when length of wire is doubled?
Property of the conductor which resists the flow of electric current is called resistivity. Resistance for a particular material is unique. When length is doubled resistance becomes double and current flow reduces to half. This is the reason for the decrease in ammeter reading.
What is electrical resistance in a series?
The total resistance of a series circuit is equal to the sum of individual resistances. Voltage applied to a series circuit is equal to the sum of the individual voltage drops. The voltage drop across a resistor in a series circuit is directly proportional to the size of the resistor.
What is electrical resistance in a series electrical circuit?
It is basically resistance for a given area of cross-section of conductor per unit length. When length of wire is doubled, the resistance is also doubled, because resistance is directly proportional to length of wire. Hence according to ohms law for a given potential difference, the current reduces to half.
What is the highest and lowest total resistance?
Ans: Given resistances R1 =4 Ω, R2=8 Ω, R3=12Ω, and R4=24Ω. ∴ 2 Ω is the lowest total resistance.
How does the resistance of a wire vary with its area of cross section?
It is inversely proportional to the area of cross section of the wire. The more the area of cross section of the wire,the less is the resistance and the less the area,the more is the resistance.