The block's displacement (or change in position) in reference frame R during the period AL * is either upward, downward, or equal to zero? Explain. (Use the velocity arrow from section c.i. to guide your response.) Does the block have an upward, downward, or no net force? Explain. Use the acceleration arrow from section c.i. to help you answer this question: Is the net force doing more work on the block than it is taking off? Explain. Based on your responses to the preceding two questions, how would you answer this question? Test to see whether you've answered section c.iii correctly in terms of net force work done on the block.

The block's displacement (or change in position) in reference frame R during the period AL * is either upward, downward, or equal to zero? Explain. (Use the velocity arrow from section c.i. to guide your response.) Does the block have an upward, downward, or no net force? Explain. Use the acceleration arrow from section c.i. to help you answer this question: Is the net force doing more work on the block than it is taking off? Explain. Based on your responses to the preceding two questions, how would you answer this question? Test to see whether you've answered section c.iii correctly in terms of net force work done on the block.