() which phenomenon causes an object to appear bent from above the surface of one medium to below the surface of another medium? a) diffraction b) dispersion c) reflection d) refraction

Does anyone have the answers to online physics course plato course physics, semester a v3.0

What is the force that opposes motion and works against the downward pull? a) friction b) gravity c) weight d) acceleration

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