What impulse occurs when an average force of 20-N is applied by a dad to a new bike riding child for 3.5 s. b) What change in momentum does the new bike rider undergo? c) If the combined mass of the bike and the child is 32 kg and the child was initially at rest, calculate the final speed.

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