10. CALCULATE: Find the amount of power used in each of the following examples. Show your
calculations.
a. You use a force of 10 N to move a box
100 m in 10 seconds.
b. An athlete lifting weights does 900 J of
work in 1 second.
c. A truck does 30,000 J of work in
15 seconds.
d. A furniture mover uses a force of 150 N to
push a large trunk 5 m across the floor in
5 seconds.

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