A block is attached to a spring. The spring constant is 20N/m. If the spring is compressed by 10cm, what is the maximum vertical height that the block can reach when it is released? The total mass of the block and spring is 80g. (g = 9.8N/kg)

Asun-sized star will spend most of its lifetime as a: white dwarf red giant protostar main-sequence star

What is special about a dc circuit ?

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