Frequent Electric Current Questions

the magnetic field due to current carrying circular loop of radius 3cm at a point on the axis at a distance of 4cm from the centre is 54 micro tesla. what will be its value at the centre of the loop ...

A parallel plate capacitor of area 60cm^2 and separation 3mm is charged initially at 90 micro coulomb. If the medium between the plates get slightly conducting and the plate loses charge initially at the rate of 2.5 *10^-8 C ...

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in order to increase the resistance of a given wire of uniform cross section to 4 times it's value, a fraction of it's length is stretched uniformly till the full length of the wire becomes 3/2 times the original length.what ...

Copper has 1 conduction electron per atom.its density is 8.89 g/cc and its atomic wt is 63.54 g/mol. If a copper wire of diameter 1 mm carries a current of 2 A. What is drift velocity in the wire. ...

How to find the potentials at points A,B,C,D,E,F. *Image* ...

TWO CONDUCTING plates each of area A are separated by distance d and they are parallel to each other. A conducting medium of varying conductivity fills space between them. the conductivity varies linearly σ to 2σ as we move ...

A bulb is made using two filaments. A switch selects whether the filaments are used individually or in parallel. When used with a 15 V battery, the bulb can be operated at 5 W, 10 W or 15 W. What should be the resistances of ...

An unknown cell balances 300 cm of wire in a potentiometer circuit, but the balance length reduces to 280 cm when a resistance of 28 ohm is added in parallel with the cell.A standard cell of emf 1.1V balances 220 cm on the sa ...

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Q) One end of a horizontal thick wire of length 2L and radius 2R is welded to an end of another horizontal thin copper wire of length L and radius R.When the arrangement is stretched by applying forces at two ends, the ratio ...

*Image* What's the difference between (c) and (d)? ...

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A wire of resistance ' R ' and length ' L ' is connected to a d.c. source of emf V through a switch ' S ' *Image* At t = 0, the switch ' S ' is closed and at the same time an external agent starts stretching the wire such tha ...