A silver wire of 1 mm diameter has a charge of 90 coulombs flowing in 1 hours and 15 minutes. Silver contains 5.28*10^28 free electrons per cm^3. Find the current in the wire and drift velocity in the electron?

A current of 10 ampere passes through a wire having cross-sectional area 1mm^2 . The number of free electron peer 1m^3 of the conductor is 10^(28) . Find the drift velocity of electron.

A copper wire,3 mm in diameter, is wound about a cylinder whose length is 1.2 m, and diameter 10 cm, so as to cover the curved surface of the cylinder. Find the length and mass of the wire, assuming the density of copper to be 8.88g/(cm^3) .

A long straight wire carries a current of 10 ampere. An electron travels with a velocity of 5.0x10 ms parallel to the wire at 0.1 m from it and in a direction opposite to the current. What force is exerted on the electron ?.

A brooch is made with silver wire in the form of a circle with diameter 35 mm.The wire is also used in making 5 diameters which divide the circle into 10 equal sectors as shown in Fig.12.12 Find:(ii)the area of each sector of the brooch.

A brass rod of length 50 cm and diameter 3.0 mm is joined to a steel rod of the same length and diameter. What is the change in length of the combined rod at 250 ^@C , if the original lengths are at 40.0 ^@C ? Is there a ‘thermal stress’ developed at the junction? The ends of the rod are free to expand (Co-efficient of linear expansion of brass = 2.0 xx 10^-5K^-1 steel = 1.2 xx 10^-5 K^-1) .

A brooch is made with silver wire in the form of a circle with diameter 35 mm.The wire is also used in making 5 diameter which divide the circle into 10 equal sectors as shown in Fig.12.12 .Find:(i)the total length of the silver wire required.

A potential difference of 5 V is applied across a conductor of length 10 cm. If drift velocity of the electron is 2.5 x 10^-4 ms^-1 find the mobility of electron.