Question
Explain physical meaning of electric field.
✓
Answer
►Electric field is an elegant way of characterising the electrical environment of a system of charges.
►Electric field at a point in the space around a system of charges tells you the force a unit positive test charge would experience if placed at that point (without disturbing the system).
►Electric field is a characteristic of the system of charges and is independent of the test charge that you place at a point to determine the field.
►The term field in physics generally refers to a quantity that is defined at every point in space and may vary from point to point.
►Electric field is a vector field, since force is a vector quantity.
►The field picture is this: the accelerated motion of charge $q _1$ produces electromagnetic waves, which then propagate with the speed c , reach $q _2$ and cause a force on $q _2$.
►The concept of field was first introduced by Faraday.
►Electric field at a point in the space around a system of charges tells you the force a unit positive test charge would experience if placed at that point (without disturbing the system).
►Electric field is a characteristic of the system of charges and is independent of the test charge that you place at a point to determine the field.
►The term field in physics generally refers to a quantity that is defined at every point in space and may vary from point to point.
►Electric field is a vector field, since force is a vector quantity.
►The field picture is this: the accelerated motion of charge $q _1$ produces electromagnetic waves, which then propagate with the speed c , reach $q _2$ and cause a force on $q _2$.
►The concept of field was first introduced by Faraday.
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