3. How did the team of physicists
make the phonon laser?​

The electric field inside a cell membrane is 8.0mn/c. what's the force on a singly charged ion in this field?

Whithin which type of system is neither the total mass nor the total energy conserved ? a. open b. connected c. isolated d. closed

The earth's magnetic field, with a magnetic dipole moment of 8.0×1022am2, is generated by currents within the molten iron of the earth's outer core. suppose we model the core current as a 3000-km-diameter current loop made from a 1000-km-diameter “wire.” the loop diameter is measured from the centers of this very fat wire.to decide whether this is a large or a small current density, compare it to the current density of a 7.0 a current in a 2.0-mm-diameter wire.