Physics — All of D (Fields)

Gravitational Field Strength

The force per unit mass acting on a small test mass placed in a gravitational field.

Gravitational Potential

The work done against gravity per unit mass to bring a small test mass from infinity to that point in space.

Escape Speed

The minimum speed required to escape from a gravitational field.

Newton's Law of Gravitation

F = G(m1 * m2) / r^2; describes the gravitational force between two masses.

Kepler's First Law

Planetary orbits are elliptical with a star at one focus.

Kepler's Second Law

The line connecting a planet to the sun sweeps out equal areas in equal times.

Kepler's Third Law

The square of the orbital time period of a satellite is directly proportional to the cube of the semi-major axis of its orbit.

Gravitational Potential Energy

The work done against gravity to bring a small test mass from infinity to that point in space

Orbital Speed

The speed at which an object must move to maintain its orbit around another object.

Lenz's Law

The induced emf will act in such a way as to oppose the change that produced it.

Electric Potential

The work done in bringing a small test charge from a point of zero potential to a point in the field

Magnetic Flux

The product of the magnetic field strength and the area normal to the field.

Faraday's Law

The induced emf is proportional to the rate of change of magnetic flux.

gravitational field

a region of space in which an object experiences a force due to its mass

PE

-(GMm)/r

KE

(GMm)/(2r)

Total energy

-(GMm)/(2r)

gravitational potential difference

the work done in moving a mass between two points in a gravitational field

polar orbit

satellites orbit over the earth’s poles in one plane, intersecting the earth’s center, with earth rotating underneath

geosynchronous orbit

satellites stay in the same area of sky and typically follow a figure-of-eight orbit

geostationary orbit

satellites orbit above the plane of the equator at the same rotational speed as the Earth

magnetic field

exists at a point where a magnetic force acts on a magnetic pole placed at that point