Two rocks, one of mass 30 kg and the other of mass 60kg, are separated by a distance of 1.0 m. They exert a gravitational force in each other of magnitude F. Which other pair of rocks exert a force of magnitude F on each other?

Asun-sized star will spend most of its lifetime as a: white dwarf red giant protostar main-sequence star

Electromagnetic induction. a coil of wire contains n turns and has an electrical resistance r. the radius of each turn is a. initially, inside the coil there exists a uniform magnetic field of magnitude b0 parallel to the axis of the coil. the magnetic field is then reduced slowly. the current induced in the coil is i. how long does it take for the magnitude of the uniform field to drop to zero?

If element x has 99 protons how many electrons does it have