Which type of bond (ionic, covalent, or metallic) does the phrase "opposite attract" apply to best? explain.

Consider a uniformly charged ring in the xy plane, centered at the origin. the ring has radius a and positive charge qdistributed evenly along its circumference. a)what is the direction of the electric field at any point on the z axis? . b)what is the magnitude of the electric field along the positive z axis? use k in your answer, where k=14πϵ0. d)the ball will oscillate along the z axis between z=d and z=−d in simple harmonic motion. what will be the angular frequency ω of these oscillations? use the approximation d≪a to simplify your calculation; that is, assume that d2+a2≈a2. express your answer in terms of given charges, dimensions, and constants

A4.0-cm tall light bulb is placed a distance of 32.0 cm from a concave mirror having a focal length of 16.0 cm. determine the image distance

En un laboratorio, nakisha mezcla una solución de hidróxido de sodio con un indicador llamado fenolftaleína. cuando se combinan, crean una solución de color rosa. nakisha se pregunta si la mezcla de otras soluciones con fenolftaleína también creará este color rosa. ? cómo podría nakisha utilizar el proceso de investigación científica para determinar si la mezcla de otras soluciones con fenolftaleína también creará un color rosa? marque las que correspondan.