# Kerr metric: Quiz

Question 1: The natural extension to a charged, rotating body, the ________, was discovered shortly afterwards in 1965.
Kerr metricKerr–Newman metricReissner–Nordström metricBlack hole

Question 2: At close enough distances, all objects — even ________ itself — must rotate with the body; the region where this holds is called the ergosphere.
AlhazenLightOpticsPhoton

Question 3: In the ________ we write the action S in the form:
Laplace–Runge–Lenz vectorClassical mechanicsHamilton–Jacobi equationHamiltonian mechanics

Question 4: The Kerr metric describes the geometry of spacetime in the vicinity of a mass M rotating with ________ J
ForceAngular momentumEnergyRigid body

Question 5: The Weyl tensor is ________, in fact it has Petrov type D.
General relativityEinstein field equationsLinearized gravityPetrov classification

Question 6: The equation of the ________ and the time dependence of the coordinates along the trajectory (motion equation) can be found then easily and directly from these equations:
ForceCometOrbitTrajectory

Question 7: However, neither surface is a true singularity, since their apparent singularity can be eliminated in a different ________.
Coordinate systemOrthogonal coordinatesCartesian coordinate systemSpherical coordinate system

Question 8: where Q represents the body's electric charge and J represents its spin ________.
Angular momentumForceRigid bodyEnergy

Question 9: where the coordinates r,θ,φ are standard ________, and rs is the Schwarzschild radius
Spherical coordinate systemCylindrical coordinate systemCartesian coordinate systemParabolic cylindrical coordinates

Question 10: Measurement of this frame dragging effect was a major goal of the ________ experiment.
GravitomagnetismGeneral relativityHeliumGravity Probe B