(b) Using Eq. 2-2, the magnitude of the average velocity is avg38.1 m5.20 m9.02 m/s4.80 sDhvT++===(c) In our coordinate choices, a positive sign for vavgmeans that the ball is going downward. If, however, upwards had been chosen as the positive direction, then this answer in (b) would turn out negative-valued. (d) We find v0from 2102yvtgtΔ= +with t= Tand Δy= h+ D. Thus, ()209.8 m/s4.80 s5.20 m38.1 m14.5 m/s24.80s2hD gTvT=−=−=(e) Here in our coordinate choices the negative sign means that the ball is being thrown upward.74. (a) Let the height of the diving board be h. We choose downas the +ydirection and set the coordinate origin at the point where it was dropped (which is when we start the
This is the end of the preview. Sign up
access the rest of the document.