Question
A man standing on the edge of a cliff at some height throws ball straight up with initial velocity u and then throws another ball straight down with same initial speed. Which ball will hit the ground with a greater speed?
Solution
Velocity with the ball is thrown upwards = u
Velocity with which another ball is thrown down = u
Both the balls will hit the ground with the same velocity if air resistance is neglected.
Ball A:
Ball B:
Ball B is thrown upward with velocity u, therefore the first the ball rises up, after reaching the maximum height and it starts falling.
Let ball B rise up by x.
That is, the ball B rises by![<pre>uncaught exception: <b>mkdir(): Permission denied (errno: 2) in /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php at line #56mkdir(): Permission denied</b><br /><br />in file: /home/config_admin/public/felixventures.in/public/application/css/plugins/tiny_mce_wiris/integration/lib/com/wiris/util/sys/Store.class.php line 56<br />#0 [internal function]: _hx_error_handler(2, 'mkdir(): Permis...', '/home/config_ad...', 56, Array)
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.
Now ball B has to fall by a total distance of
.
Let vB be the velocity of ball B, when it reaches the ground.
Velocity with which another ball is thrown down = u
Both the balls will hit the ground with the same velocity if air resistance is neglected.
Ball A:
Ball B:
Ball B is thrown upward with velocity u, therefore the first the ball rises up, after reaching the maximum height and it starts falling.
Let ball B rise up by x.
That is, the ball B rises by
. Now ball B has to fall by a total distance of
.Let vB be the velocity of ball B, when it reaches the ground.
