Question

Name Student ID Score last first IV. [18 points total] A block oscillates on a spring as shown at right. At time , the block moves downward at its maximum speed; at time t2, the spring is stretched and the block is at its turn-around point. A. [3 pts] In the space at right, draw a free-body diagram for the block at instant. Label the forces to indicate (1) the type of force, (2) the object exerting the force, and (3) the object on which the force is Free-body diagram for the block exerted B. [3 pts] Rank the magnitudes of the forces on your frec-body diagram for the block at instant . Explain. C. [4 pts] At the instant 12, is the magnitude of the force by the block on the spring greater than, less than, or equal to the magnitude of the force by the spring on the block? Explain D. [4 pts] Over the interval from t to t2, is the work done by the spring on the block positive, negative or zero? Explain. E. [4 pts] Consider the system consisting of the block only. Over the interval from /j to i2, is Wnet ext, the net work done by external force on the system positive, negative, or zero? Explain. Physies 121A, Autumn 2017 Exam 2 ME-UWA121A174T-E2(FNL,WCE)

Answer 1

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