Factors Affecting Resistance

Q. The electrical resistance of a mercury column in a cylindrical container is $R$. When all of the mercury is poured out into another cylindrical container of half the radius of cross section, the resistance of the new mercury column will be ______.

1. $2R$
2. $4R$
3. $8R$
4. $16R$

Q. The inverse of resistivity is .

1. conductance
2. conductivity
3. resistance
4. specific resistance

Q. A longer wire has more resistance than a shorter wire of the same thickness and same material.

1. True
2. False

Q.

The resistance of the wire varies inversely as

1. Area of cross-section

2. Resitivity

3. Length

4. Temperature

Q.

A thick wire and a thin wire made from same material and of same length are connected one by

Q.

The resistance of a wire does not depend on the area of its cross-section.

1. Length of conductor

2. Area of cross-section

Q. What is the resistance of a wire if its length is doubled,

1. becomes twice
2. becomes thrice
3. remains same
4. becomes half

Q.

A wire of resistance 3 ohm and length 10 cm is stretched to length 30 cm. Assuming that it has a uniform cross section, what will be its new resistance?

Q. Masses of three wires of copper are in the ratio 1 : 3 : 5 and their lengths are in the ratio of 5 : 3 : 1. The ratio of their electrical resistances are ___.

1. 5 : 3 : 1
2. 1 : 15 : 125
3. 125 : 15 : 1
4. 1 : 3 : 5

Q. Will current flow more easily through a thick wire or a thin wire of the same material when connected to the same source? Give reason for your answer.

Q. ntif wire is streatched soits length increases20%more than initial length % incresesinresistence of wire willbe, terminalP.Dof a cell always les than its emfn

Q. The reciprocal of resistivity of a conductor is

1. conductance
2. capacitance
3. conductivity
4. none of these

Q.

A wire of resistance 3 ohm and length 10 cm is stretched to length 30 cm. Assuming that it has a uniform cross section, what will be its new resistance?

Q.

what does resistance mean?