Answer:
the velocity of a ball at highest point is 8.5m/s
Step-by-step explanation:
: The Freefall Problem
Xue,is standing on the roof of a building. Emily is standing below and tosses a ball straight upwards to Xue. It travels up past
Xue, comes back down and Xue reaches out and catches it. Xue catches the ball 6.0 m above Emily’s hands. The ball was
travelling at 12.0 m/s upwards the moment it left Emily’s hand. We would like to know how much time this trip takes.
1. Represent. Complete part A below. Indicate the y-origin for position measurements and draw a sign convention where
upwards is positive. Label the important events.
2. Represent. Complete part C below. Make sure the two graphs line-up vertically. Draw a single dotted vertical line
through the graphs indicating the moment when the ball is at its highest.
A: Pictorial Representation
Sketch, coordinate system, label givens, conversions, describe events
Event 1:
Event 2:
Event 3:
C: Physics Representation
Motion diagram, motion graphs, key events
The total length of the path traveled by an object is the distance. The change in position, from one event to another is the
displacement. Distance is a scalar quantity and displacement is a vector quantity.
3. Reason. Explain why this in this example it is relatively easy to find the displacement, but harder to find the distance.
4. Reason. The BIG 5 equations are valid for any interval of motion where the acceleration is uniform. Does the ball
accelerate uniformly during events 1 and 3? Explain D: Mathematical Representation
Describe steps, complete equations, substitutions with final statement isThere are multiple ways of solving…one
will require the use of the quadratic formula.
The other way will take additional steps.
x = -b+-under root b^2-4ac/2a