3. Gravitational and Eletric Fields Flashcards
What is meant by permitivity of free space?
a physical constant that reflects the ability of electrical fields to pass through a classical vacuume
What is meant by an electric field?
A 3D space where charged particles experience the electrostatic force.
What do electric field lines show us?
The direction that a positive charge would make if placed in the field.
What direction do filed lines go?
positive to negative.
What happens to the magnitude of electrostatic force when an electron moves through a uniform electric field?
the electrostatic force is unchanged
Difine electric field strength
the force per unit charge on a postivive charge
In terms of electric field reffer to coulombs law.
-The force that is expreienced between two charges
-The force obays inverse square law where the distances are meassured from their centers
In terms of electric field reffer to electric field lines.
-They show direction in which a charge will feel a force
- The arrows show direction form postivive towards less positive/negaitive
In terms of electric field reffer to Electric potential.
-Work done per unit charge to bring a test charge from infinity to that point
-Scalar quantity beacause work done is also
-They are positive for repulsion as you do work against the field
In terms of electric field reffer to equipotential lines.
-Where electric potential is the same at all points on the line
-Straight parrallel line- uniform
- Circles around Q - radial
- No work is done when moving a charge along an equipotential.
Escape Velocity:
The minimum velocity required by an object to be able to escape a gravitational field of a mass when projected vertically from its surface.
Gravitational Field:
A region surrounding a mass in which any other object with mass will experience an attractive force.
Gravitational Field Strength:
The force per unit mass exerted on a small test mass placed within the field.
Gravitational Potential, V (at a point in the field):
The work done per unit mass required to move 1kg mass from infinity to that point.
What happens to emf when a coil moves in a magnetic field. Needs editing
(As the coil moves) there is a rate of change of flux through v1 The first part ie the induced emf is the coil v1 (owtte)
proportional to the rate of change of flux linkage may be given in a number of wa
The induced emf is proportional to the rate of change of flux (linkage) so the (magnitude) of the emf decreases
