In which condition EMF will be induced in loop.
Situation-S1: A loop is moving with uniform velocity in a uniform magnetic field perpendicular
to its plane.
Situation-S2: A loop is moving with non-uniform velocity in a uniform magnetic field
perpendicular to its plane.
Situation-S3: A loop is rotating about its diameter in a uniform magnetic field.
Situation-S4: Area of loop is changing in a uniform magnetic field.
In which condition EMF will be induced in loop.
Situation-S1: A loop is moving with uniform velocity in a uniform magnetic field perpendicular
to its plane.
Situation-S2: A loop is moving with non-uniform velocity in a uniform magnetic field
perpendicular to its plane.
Situation-S3: A loop is rotating about its diameter in a uniform magnetic field.
Situation-S4: Area of loop is changing in a uniform magnetic field.
S2,S3
S1,S3
S2,S4
S3,S4
The Correct Option is D
Solution and Explanation
S1, S2 \(\to\) The Flux remains constant
S3 \(\to\) Φ= BA cos θ [Here, θ is changing]
S4 \(\to\) The area is changing \(\to\) The EMF induces
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Concepts Used:
Magnetic Field
The magnetic field is a field created by moving electric charges. It is a force field that exerts a force on materials such as iron when they are placed in its vicinity. Magnetic fields do not require a medium to propagate; they can even propagate in a vacuum. Magnetic field also referred to as a vector field, describes the magnetic influence on moving electric charges, magnetic materials, and electric currents.
A magnetic field can be presented in two ways.
- Magnetic Field Vector: The magnetic field is described mathematically as a vector field. This vector field can be plotted directly as a set of many vectors drawn on a grid. Each vector points in the direction that a compass would point and has length dependent on the strength of the magnetic force.
- Magnetic Field Lines: An alternative way to represent the information contained within a vector field is with the use of field lines. Here we dispense with the grid pattern and connect the vectors with smooth lines.
Properties of Magnetic Field Lines
- Magnetic field lines never cross each other
- The density of the field lines indicates the strength of the field
- Magnetic field lines always make closed-loops
- Magnetic field lines always emerge or start from the north pole and terminate at the south pole.