Physics-
General
Easy
Question
A metallic block carrying current I is subjected to a uniform magnetic induction 
as shown in the figure. The moving charges experience a force 
given by ........... which results in the lowering of the potential of the face ........ Assume the speed of the carriers to be v
, ABCD
- , EFGH
, ABCD
- , EFGH
, ABCD
, EFGH
, ABCD
, EFGH
The correct answer is: , ABCD
As the block is of metal, the charge carriers are electrons, so for current along positive x-axis, the electrons are moving along negative x-axis, i.e. 
and as the magnetic field is along the y-axis, i.e. 
so 
for this case yield 
i.e., 
[As 
]
As force on electrons is towards the face ABCD, the electrons will accumulate on it an hence it will acquire lower potential
Related Questions to study
physics-
A conducting loop carrying a current I is placed in a uniform magnetic field pointing into the plane of the paper as shown. The loop will have a tendency to
A conducting loop carrying a current I is placed in a uniform magnetic field pointing into the plane of the paper as shown. The loop will have a tendency to
physics-General
physics-
Wires 1 and 2 carrying currents 
and 
respectively are inclined at an angle 
to each other. What is the force on a small element dl of wire 2 at a distance of r from wire 1 (as shown in figure) due to the magnetic field of wire1
Wires 1 and 2 carrying currents and respectively are inclined at an angle to each other. What is the force on a small element dl of wire 2 at a distance of r from wire 1 (as shown in figure) due to the magnetic field of wire1
physics-General
physics-
A and B are two conductors carrying a current i in the same direction. x and y are two electron beams moving in the same direction
A and B are two conductors carrying a current i in the same direction. x and y are two electron beams moving in the same direction
physics-General
physics-
An elastic circular wire of length l carries a current I. It is placed in a uniform magnetic field 
(Out of paper) such that its plane is perpendicular to the direction of . The wire will experience
An elastic circular wire of length l carries a current I. It is placed in a uniform magnetic field (Out of paper) such that its plane is perpendicular to the direction of . The wire will experience
physics-General
physics-
For a positively charged particle moving in a x-y plane initially along the x-axis, there is a sudden change in its path due to the presence of electric and/or magnetic fields beyond P. The curved path is shown in the x-y plane and is found to be non-circular. Which one of the following combinations is possible
For a positively charged particle moving in a x-y plane initially along the x-axis, there is a sudden change in its path due to the presence of electric and/or magnetic fields beyond P. The curved path is shown in the x-y plane and is found to be non-circular. Which one of the following combinations is possible
physics-General
physics-
A non-planar loop of conducting wire carrying a current I is placed as shown in the figure. Each of the straight sections of the loop is of length 2a. The magnetic field due to this loop at the point P (a,0,a) points in the direction
A non-planar loop of conducting wire carrying a current I is placed as shown in the figure. Each of the straight sections of the loop is of length 2a. The magnetic field due to this loop at the point P (a,0,a) points in the direction
physics-General
physics-
An infinitely long conductor PQR is bent to form a right angle as shown. A current I flows through PQR The magnetic field due to this current at the point M is H1. Now another infinitely long straight conductor QS is connected at Q so that the current is I/2 in QR as well as in QS, The current in PQ remaining unchanged. The magnetic field at M is now 
The ratio 
is given by
An infinitely long conductor PQR is bent to form a right angle as shown. A current I flows through PQR The magnetic field due to this current at the point M is H1. Now another infinitely long straight conductor QS is connected at Q so that the current is I/2 in QR as well as in QS, The current in PQ remaining unchanged. The magnetic field at M is now The ratio is given by
physics-General
physics-
A cell is connected between the points A and C of a circular conductor ABCD of centre O with angle A
. If 
and 
are the magnitudes of the magnetic fields at O due to the currents in ABC and ADC respectively, the ratio 
is
A cell is connected between the points A and C of a circular conductor ABCD of centre O with angle A. If and are the magnitudes of the magnetic fields at O due to the currents in ABC and ADC respectively, the ratio is
physics-General
physics-
The magnetic field at the centre of a circular coil of radius r is 
times that due to a long straight wire at a distance r from it, for equal currents. Figure here shows three cases : in all cases the circular part has radius r and straight ones are infinitely long. For same current the B field at the centre P in cases 1, 2, 3 have the ratio
The magnetic field at the centre of a circular coil of radius r is times that due to a long straight wire at a distance r from it, for equal currents. Figure here shows three cases : in all cases the circular part has radius r and straight ones are infinitely long. For same current the B field at the centre P in cases 1, 2, 3 have the ratio
physics-General
physics-
The voltage gain of the following amplifier is
The voltage gain of the following amplifier is
physics-General
physics-
The magnetic field in the cylindrical region shown in figure increases at a constant rate of 20 mT/sec. Each side of the square loop ABCD has a length of 1 cm and resistance of 4W. Find the current in the wire AB if the switch S is closed
The magnetic field in the cylindrical region shown in figure increases at a constant rate of 20 mT/sec. Each side of the square loop ABCD has a length of 1 cm and resistance of 4W. Find the current in the wire AB if the switch S is closed
physics-General
physics-
A pair of parallel conducting rails lie at right angle to a uniform magnetic field of 2.0 T as shown in the fig. Two resistors 10 
and 5 are to slide without friction along the rail. The distance between the conducting rails is 0.1 m. Then
A pair of parallel conducting rails lie at right angle to a uniform magnetic field of 2.0 T as shown in the fig. Two resistors 10 and 5 are to slide without friction along the rail. The distance between the conducting rails is 0.1 m. Then
physics-General
physics-
Two coils P and Q are placed co-axially and carry current I and I' respectively
Two coils P and Q are placed co-axially and carry current I and I' respectively
physics-General
physics-
An alternating voltage of 141.4V (rms) is applied to a vacuum diode as shown in the figure. The maximum potential difference across the condenser will be
An alternating voltage of 141.4V (rms) is applied to a vacuum diode as shown in the figure. The maximum potential difference across the condenser will be
physics-General
physics-
The diagram of a logic circuit is given below. The output F of the circuit is represented by
The diagram of a logic circuit is given below. The output F of the circuit is represented by
physics-General
