Passage I

Students conducted an experiment to see how jumping on a merry-go-round affects how fast it spins. In each case an empty spinning merry-go-round was approached by a student who ran in the direction shown in Figure 1 and then jumped on the edge. Several trials, each consisting of three runs, were performed using students of different masses running at different speeds, and different initial spin rates for the merry-go-round, given in revolutions per minute (rpm). The results are shown in Table 1.

5. If a student runs at a certain speed called the critical speed, the final spin rate of the merry-go-round will equal the initial spin rate regardless of the student's mass. For an initial spin rate of 10 rpm, the critical speed is:

Answer and Explanation

Your Answer is

Correct Answer is A

Explanation

The definition of critical speed is that when the students jump up at this speed, the spin rate will not change. We found that when the spin was set to 10, the final spin rate did not change when all the student speeds of trail 3 were 1.36. So the critical speed is 1.36