Physics-
General
Easy
Question
The variation of induced emf (E) with time (t) in a coil if a short bar magnet is moved along its axis with a constant velocity is best represented as
The correct answer is:
As the magnet moves towards the coil, the magnetic flux increases (nonlinearly). Also there is a change in polarity of induced emf when the magnet passes on to the other side of the coil
Related Questions to study
physics-
The graph Shows the variation in magnetic flux 
with time through a coil. Which of the statements given below is not correct
The graph Shows the variation in magnetic flux with time through a coil. Which of the statements given below is not correct
physics-General
physics-
A simple pendulum with bob of mass m and conducting wire of length L swings under gravity through an angle 
. The earth’s magnetic field component in the direction perpendicular to swing is B. Maximum potential difference induced across the pendulum is
A simple pendulum with bob of mass m and conducting wire of length L swings under gravity through an angle . The earth’s magnetic field component in the direction perpendicular to swing is B. Maximum potential difference induced across the pendulum is
physics-General
physics-
The network shown in the figure is a part of a complete circuit. If at a certain instant the current i is 5 A and is decreasing at the rate of 
then 
is
The network shown in the figure is a part of a complete circuit. If at a certain instant the current i is 5 A and is decreasing at the rate of then is
physics-General
physics-
The figure shows three circuits with identical batteries, inductors, and resistors. Rank the circuits according to the current through the battery (i) just after the switch is closed and (ii) a long time later, greatest first
The figure shows three circuits with identical batteries, inductors, and resistors. Rank the circuits according to the current through the battery (i) just after the switch is closed and (ii) a long time later, greatest first
physics-General
physics-
What is the mutual inductance of a two-loop system as shown with centre separation l
What is the mutual inductance of a two-loop system as shown with centre separation l
physics-General
Maths-
Assertion (A) : The length of latus rectum in fig is 24/5.
Reason (R) : If l 1 and l2are length of segments of a focal chord of a parabola, then its latus rectum is 
.
Assertion (A) : The length of latus rectum in fig is 24/5.
Reason (R) : If l 1 and l2are length of segments of a focal chord of a parabola, then its latus rectum is .
Maths-General
maths-
Assertion: Through (
+ 1) there can not the more than one normal to the parabola y2 = 4x if + 
< 2.
Reason: The point ( + 1) lie out side the parabola for all 
1.
Assertion: Through ( + 1) there can not the more than one normal to the parabola y2 = 4x if + < 2.
Reason: The point ( + 1) lie out side the parabola for all 1.
maths-General
maths-
The point of intersection of the tangents at the ends of the latus rectum of the parabola y2 = 4x is .
The point of intersection of the tangents at the ends of the latus rectum of the parabola y2 = 4x is .
maths-General
maths-
If a ≠ 0 and the line 2bx + 3cy + 4d = 0 passes through the points of intersection of the parabolas 
= 4ax and 
= 4ay, then-
If a ≠ 0 and the line 2bx + 3cy + 4d = 0 passes through the points of intersection of the parabolas = 4ax and = 4ay, then-
maths-General
maths-
If M is the foot of perpendicular from a point P of a parabola y2 = 4ax to its directrix and SPM is an equilateral triangle, where S is the focus. Then SP equal to-
If M is the foot of perpendicular from a point P of a parabola y2 = 4ax to its directrix and SPM is an equilateral triangle, where S is the focus. Then SP equal to-
maths-General
physics-
A conducting rod AC of length 4l is rotated about a point O in a uniform magnetic field 
directed into the paper. AO = l and OC = 3l. Then
A conducting rod AC of length 4l is rotated about a point O in a uniform magnetic field directed into the paper. AO = l and OC = 3l. Then
physics-General
physics-
A wire cd of length l and mass m is sliding without friction on conducting rails ax and by as shown. The vertical rails are connected to each other with a resistance R between a and b. A uniform magnetic field B is applied perpendicular to the plane abcd such that cd moves with a constant velocity of
A wire cd of length l and mass m is sliding without friction on conducting rails ax and by as shown. The vertical rails are connected to each other with a resistance R between a and b. A uniform magnetic field B is applied perpendicular to the plane abcd such that cd moves with a constant velocity of
physics-General
physics-
A rectangular loop with a sliding connector of length l = 1.0 m is situated in a uniform magnetic field B = 2T perpendicular to the plane of loop. Resistance of connector is r = 2
. Two resistance of 6 and 3 are connected as shown in figure. The external force required to keep the connector moving with a constant velocity v = 2m/s is
A rectangular loop with a sliding connector of length l = 1.0 m is situated in a uniform magnetic field B = 2T perpendicular to the plane of loop. Resistance of connector is r = 2. Two resistance of 6 and 3 are connected as shown in figure. The external force required to keep the connector moving with a constant velocity v = 2m/s is
physics-General
physics-
Plane figures made of thin wires of resistance R = 50 milli ohm/metre are located in a uniform magnetic field perpendicular into the plane of the figures and which decrease at the rate dB/dt = 0.1 m T/s. Then currents in the inner and outer boundary are. (The inner radius a = 10 cm and outer radius b = 20 cm)
Plane figures made of thin wires of resistance R = 50 milli ohm/metre are located in a uniform magnetic field perpendicular into the plane of the figures and which decrease at the rate dB/dt = 0.1 m T/s. Then currents in the inner and outer boundary are. (The inner radius a = 10 cm and outer radius b = 20 cm)
physics-General
physics-
A highly conducting ring of radius R is perpendicular to and concentric with the axis of a long solenoid as shown in fig. The ring has a narrow gap of width d in its circumference. The solenoid has cross sectional area A and a uniform internal field of magnitude B0. Now beginning at t = 0, the solenoid current is steadily increased to so that the field magnitude at any time t is given by B(t) = B0 + at where 
. Assuming that no charge can flow across the gap, the end of ring which has excess of positive charge and the magnitude of induced e.m.f. in the ring are respectively
A highly conducting ring of radius R is perpendicular to and concentric with the axis of a long solenoid as shown in fig. The ring has a narrow gap of width d in its circumference. The solenoid has cross sectional area A and a uniform internal field of magnitude B0. Now beginning at t = 0, the solenoid current is steadily increased to so that the field magnitude at any time t is given by B(t) = B0 + at where . Assuming that no charge can flow across the gap, the end of ring which has excess of positive charge and the magnitude of induced e.m.f. in the ring are respectively
physics-General
