Physics-
General
Easy
Question
A metallic rod of length ‘l’ is tied to a string of length 2l and made to rotate with angular speed 
on a horizontal table with one end of the string fixed. If there is a vertical magnetic field ‘B’ in the region, the e.m.f. induced across the ends of the rod is:
The correct answer is:
Related Questions to study
physics-
A rectangular loop has a sliding connector PQ of length 
and resistance R 
and it is moving with a speed v as shown. The set-up is placed in a uniform magnetic field going into the plane of the paper. The three currents 
and I are :
A rectangular loop has a sliding connector PQ of length and resistance R and it is moving with a speed v as shown. The set-up is placed in a uniform magnetic field going into the plane of the paper. The three currents and I are :
physics-General
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An inductor of inductance L = 400 mH and resistors of resistances R1 = 2 and R2 = 2 are connected to a battery of emf 12 V as shown in the figure. The internal resistance of the battery is negligible. The switch S is closed at t = 0. The potential drop across L as a function of time is 
An inductor of inductance L = 400 mH and resistors of resistances R1 = 2 and R2 = 2 are connected to a battery of emf 12 V as shown in the figure. The internal resistance of the battery is negligible. The switch S is closed at t = 0. The potential drop across L as a function of time is
physics-General
physics-
An inductor (L = 100 mH), a resistor (R = 100 ) and a battery (E = 100 V) are initially connected in series as shown in the figure. After a long time the battery is disconnected after short circuiting the points A and B. The current in the circuit, 1 ms after the short circuit is:
An inductor (L = 100 mH), a resistor (R = 100 ) and a battery (E = 100 V) are initially connected in series as shown in the figure. After a long time the battery is disconnected after short circuiting the points A and B. The current in the circuit, 1 ms after the short circuit is:
physics-General
physics-
One conducting u tube can slide inside another as shown in figure, maintaining electrical contacts between the tubes. The magnetic field B is perpendicular to the plane of the figure. If each tube moves towards the other at a constant speed v, then the emf induced in the circuit in terms of B,
and v, where 
is the width of each tube, will be
One conducting u tube can slide inside another as shown in figure, maintaining electrical contacts between the tubes. The magnetic field B is perpendicular to the plane of the figure. If each tube moves towards the other at a constant speed v, then the emf induced in the circuit in terms of B, and v, where is the width of each tube, will be
physics-General
chemistry-
Aqueous solution of salt of strong base and weak acid
Aqueous solution of salt of strong base and weak acid
chemistry-General
physics-
Figure shows a conducting rod of negligible resistance that can slide on smooth U-shaped rail made of wire of resistance 1 /m. Position of the conducting rod at t = 0 is shown. A time t dependent magnetic field B = 2t Tesla is switched on at t = 0
Following situation of the previous question, the magnitude of the force required to move the conducting rod at constant speed 5 cm/s at the same instant t = 2s, is equal to
Figure shows a conducting rod of negligible resistance that can slide on smooth U-shaped rail made of wire of resistance 1 /m. Position of the conducting rod at t = 0 is shown. A time t dependent magnetic field B = 2t Tesla is switched on at t = 0
Following situation of the previous question, the magnitude of the force required to move the conducting rod at constant speed 5 cm/s at the same instant t = 2s, is equal to
physics-General
physics-
Figure shows a conducting rod of negligible resistance that can slide on smooth U-shaped rail made of wire of resistance 1 /m. Position of the conducting rod at t = 0 is shown. A time t dependent magnetic field B = 2t Tesla is switched on at t = 0
The current in the loop at t = 0 due to induced emf is
Figure shows a conducting rod of negligible resistance that can slide on smooth U-shaped rail made of wire of resistance 1 /m. Position of the conducting rod at t = 0 is shown. A time t dependent magnetic field B = 2t Tesla is switched on at t = 0
The current in the loop at t = 0 due to induced emf is
physics-General
physics-
An inductor having self-inductance L with its coil resistance R is connected across a battery of emf 
. When the circuit is in steady state at t = 0 an iron rod is inserted into the inductor due to which its inductance becomes n L (n > 1)
When again circuit is in steady state, the current in it is :
An inductor having self-inductance L with its coil resistance R is connected across a battery of emf . When the circuit is in steady state at t = 0 an iron rod is inserted into the inductor due to which its inductance becomes n L (n > 1)
When again circuit is in steady state, the current in it is :
physics-General
physics-
An inductor having self-inductance L with its coil resistance R is connected across a battery of emf . When the circuit is in steady state at t = 0 an iron rod is inserted into the inductor due to which its inductance becomes n L (n > 1)
After insertion of the rod, current in the circuit:
An inductor having self-inductance L with its coil resistance R is connected across a battery of emf . When the circuit is in steady state at t = 0 an iron rod is inserted into the inductor due to which its inductance becomes n L (n > 1)
After insertion of the rod, current in the circuit:
physics-General
physics-
An inductor having self-inductance L with its coil resistance R is connected across a battery of emf . When the circuit is in steady state at t = 0 an iron rod is inserted into the inductor due to which its inductance becomes nL (n > 1)
After insertion of rod which of the following quantities will change with time?
1) Potential difference across terminals A and B.
2) Inductance.
3) Rate of heat produced in coil
An inductor having self-inductance L with its coil resistance R is connected across a battery of emf . When the circuit is in steady state at t = 0 an iron rod is inserted into the inductor due to which its inductance becomes nL (n > 1)
After insertion of rod which of the following quantities will change with time?
1) Potential difference across terminals A and B.
2) Inductance.
3) Rate of heat produced in coil
physics-General
physics-
Statement-1 : Consider the arrangement shown below. A smooth conducting rod, CD, is lying on a smooth U-shaped conducting wire making good electrical contact with it. The U-shape conducting wire is fixed and lies in horizontal plane. There is a uniform and constant magnetic field B in vertical direction (perpendicular to plane of page in figure). If the magnetic field strength is decreased, the rod moves towards right.
Statement-2 : In the situation of statement-1, the direction in which the rod will slide is that which tends to maintain constant flux through the loop. Providing a larger loop area counteracts the decrease in magnetic flux. So the rod moves to the right independent of the fact that the direction of magnetic field is into the page or out of the page.
Statement-1 : Consider the arrangement shown below. A smooth conducting rod, CD, is lying on a smooth U-shaped conducting wire making good electrical contact with it. The U-shape conducting wire is fixed and lies in horizontal plane. There is a uniform and constant magnetic field B in vertical direction (perpendicular to plane of page in figure). If the magnetic field strength is decreased, the rod moves towards right.
Statement-2 : In the situation of statement-1, the direction in which the rod will slide is that which tends to maintain constant flux through the loop. Providing a larger loop area counteracts the decrease in magnetic flux. So the rod moves to the right independent of the fact that the direction of magnetic field is into the page or out of the page.
physics-General
physics-
Statement-1 : A resistance R is connected between the two ends of the parallel smooth conducting rails. A conducting rod lies on these fixed horizontal rails and a uniform constant magnetic field B exists perpendicular to the plane of the rails as shown in the figure. If the rod is given a velocity v and released as shown in figure, it will stop after some time. The total work done by magnetic field is negative.
Statement-2 : If force acts opposite to direction of velocity its work done is negative.
Statement-1 : A resistance R is connected between the two ends of the parallel smooth conducting rails. A conducting rod lies on these fixed horizontal rails and a uniform constant magnetic field B exists perpendicular to the plane of the rails as shown in the figure. If the rod is given a velocity v and released as shown in figure, it will stop after some time. The total work done by magnetic field is negative.
Statement-2 : If force acts opposite to direction of velocity its work done is negative.
physics-General
physics-
A conducting rod of length is moved at constant velocity ‘
’ on two parallel, conducting, smooth, fixed rails, that are placed in a uniform constant magnetic field B perpendicular to the plane of the rails as shown in figure. A resistance R is connected between the two ends of the rail. Then which of the following is/are correct :
A conducting rod of length is moved at constant velocity ‘ ’ on two parallel, conducting, smooth, fixed rails, that are placed in a uniform constant magnetic field B perpendicular to the plane of the rails as shown in figure. A resistance R is connected between the two ends of the rail. Then which of the following is/are correct :
physics-General
physics-
In the circuit diagram shown
In the circuit diagram shown
physics-General
physics-
A solenoid having an iron core has its terminals connected across an ideal DC source and it is in steady state. If the iron core is removed, the current flowing through the solenoid just after removal of rod
A solenoid having an iron core has its terminals connected across an ideal DC source and it is in steady state. If the iron core is removed, the current flowing through the solenoid just after removal of rod
physics-General
