10.1 Gravitational And Electrical Potential Flashcards
What is gravitational potential at a point?
The work done per unit mass to move a point mass from infinity to that point at a small constant speed V = W/m the unit of gravitational potential Jkg-1
What is electric potential at a point?
The work done per unit charge to move a positive point charge from infinity to that point at a small constant speed V = W/q the unit of gravitational potential JC-1
What is an equipotential surface?
A surface on which the potential is the same everywhere.
What is the gravitational potential energy at a point?
The work done to move a point mass from infinity to that point in a gravitational field.
What is the electrical potential energy at a point?
The work done to move a positive point charge from infinity to that point in an electrical field.
What is gravitational potential?
A scalar quantity, the work done in moving a mass in a gravitational field is independent of the path followed, the formula is V = -GM/r
What is electrical potential?
A scalar quantity, the work done in moving a positive point charge in an electric field is independent of the path followed, the formula is V = kQ/r
How can you find gravitational or electrical potential from more than one mass or charge?
Because potential is a scalar quantity we find potential from each mass or charge separately and add them.
What is gravitational work?
To move a mass from one point to another in a gravitational field requires that work to be done. The work done on the mass is
W = mdeltaV.
What is the formula for the world done by the gravitational force?
W = -mdeltaV
What is electrical work?
To move a charge from one point to another in an electrical field requires that work to be done. The work done on the mass is
W = qdeltaV.
What is the formula for the world done by the electric force?
W = -qdeltaV
What is field strength?
The negative gradient of the potential.
On a graph of potential versus distance what is the gradient?
The negative of the field strength.
What is the formula for electric field strength?
E = kQ/r^2
