An alpha particle (which has two protons) is sent directly toward a target nucleus with 90 protons. the alpha particle has a kinetic energy of 0.45 pj when far away. what is the least center-to-center distance that the alpha particle will be from the target nucleus, assuming that the nucleus does not move?

Ablock of steel has a density of 0.29lbs per cubic inch. if the block has dimensions of 1 inch by 1 inch by 3 inches, what is its weight? a. 0.29lbs b. 0.58lbs c. 0.87lbs d. 1lbs

An equinox occurs when a. neither end of earth's axis is tilted toward or away from the sun. b. the north end of earth's axis is tilted away from the sun. c. the north end of earth's axis is tilted toward the sun. d. earth's axis is parallel to the sun's rays. select the best answer from the choices provided a b c d

Consider each of the electric- and magnetic-field orientations given next. in each case, what is the direction of propagation of the wave? a)\vec ein the +xdirection,\vec bin the +ydirection. choose+ x direction- x direction+ y direction- y direction+ z direction- z direction b)\vec ein the -y direction,\vec bin the +x choose+ x direction- x direction+ y direction- y direction+ z direction- z direction c)\vec ein the +z direction,\vec bin the -x direction. choose+ x direction- x direction+ y direction- y direction+ z direction- z direction d)\vec ein the +y direction,\vec bin the -z direction. choose+ x direction- x direction+ y direction- y direction+ z direction- z direction