Question #adb98

1 Answer
Jul 25, 2016

Given

#u->"The initial upward velocity of the ball"=+19.8m/s#

#h->"Downward displacement in t=5 s"= "height of tower"#

#g->"Acceleration due to gravity"=-9.8m/s^2#

Applying equation of motion

#h=u*t+1/2g *t^2#

#=>h=19.6*5-1/2*9.8*5^2#

#=>h=98-4.9*25=-24.5m#

Velocity of the ball on reaching the ground

#v= u+g*t#

#=>v=19.6-9.8*5=19.6-49#
#=-29.4m/s#

Negative sign indicates that direction of final displacement and velocity are opposite to the direction of initial velcity.