When electrons drift in a metal from lower to higher potential, does it mean that all the free electrons of the metal are moving in the same direction ?
When an electric field is applied, the net drift of electrons will be from lower to higher potential while local electrons tends to collide with ions resulting in change of direction. So, not all free electrons of metal will move in similar direction since drift velocity superpose only over random velocities of electrons.
In the circuit shown in the figure, find the total resistance of the circuit and the current in the arm CD.
Calculate the current drawn from the battery by the network of resistors shown in the figure.
How does one explain increase in resistivity of a metal with increase in temperature ?
In the two electric circuits shown in the figure, determine the readings of ideal ammeter (A) and the ideal voltmeter (V).
Plot a graph showing the variation of current I versus resistance R, connected to a cell of emf E and internal resistance r.
Figure shows a point charge + Q, located at a distance R/2 from the centre of a spherical metal shell. Draw the electric field lines for the given system.
Two point charges ‘q1’ and ‘q2’ are placed at a distance ‘d’ apart as shown in the figure. The electric field intensity is zero at a point ‘P’ on the line joining them as shown. Write two conclusions that you can draw from this.
An electron is accelerated through a potential difference V. Write the expression for its final speed, if it was initially at rest.
Two equal balls having equal positive charge ‘q’ coulombs are suspended by two insulating strings of equal length. What would be the effect on the force when a plastic sheet is inserted between the two ?
Why is the use of ac voltage preferred over dc voltage ? Give two reasons.
Why do the electrostatic field lines not form closed loops ?
Nichrome and copper wires of same length and same radius are connected in series. Current I is passed through them. Which wire gets heated up more ? Justify your answer.