released. b) The time of flight will be twice the time it takes to get to its highest point.
These statements are related to projectile motion and can be proven using kinematic equations. We can split the trajectory of an object thrown vertically up into three components: the object at its initial height (point A), the object at its max height (point B), and the object back at its initial height (point C). Knowing that the velocity of the object at its max height is zero, lets solve for initial velocity (when it is released) using the kinematic equation vf=vi+at for the object from Point A to Point B. -->0=vi-9,8t-->vi=9.8t. Now lets do the same from point B to point C. This time, the initial velocity is zero since were starting at max height. -->vf=0-9.8t-->vf=-9.8t. We see that these velocities are the same in both instances however in opposite directions, initially the object is going up, when it comes back, its going down. Try the same approach for part B with one of the kinematic equations and see if you get it.