28. which of the following statements is true? a. an ideal metal conducts because each electron ‘belongs’ to every nucleus in the crystal lattice, while in an ideal insulator, each electron is localized to a single nucleus. b. metals conduct much better than insulators because, per gram of material, metals have orders of magnitude more electrons. c. at sufficiently low temperatures, (intrinsic) semi-conductors are effectively insulators.

sonar - device which is used to find the submit submarines, sankalp ship. sonar waves consists of a transmitter and detector which are installed in the observation centre on board of a ship. the ultrasonic waves are sent into the sea at high frequency about 1000 khz in all direction.

the simple machine has three main features. they are:

fulcrum is the center point or pivot point of the machine. effort is input force/ applied force. load is external force/ output.

the keisha 's machine labels are

x : load

y: fulcrum

z: lever

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary