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(14) physics science
quiz 2
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arunner is running to the left with a speed of 8.0 — when she speeds up with constant acceleration for
2.0 s to reach the finish line. the runner's final speed is 9.9 to the left.
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what was the runner's acceleration as she sped up to the finish line?

You are given a vector a = 125i and an unknown vector b that is perpendicular to a. the cross-product of these two vectors is a × b = 98k. what is the y-component of vector b?

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

By what primary heat transfer mechanism does the sun warm the earth?