Question

A kangaroo is capable of jumping to a height of $2.62m$. Determine the takeoff speed of the kangaroo.

• A. $7.17m$
  
• B. $7.7m/s$
  
• C. $7.1m/s$
  
• D. $7.17m/s$
  

Answer 1

The correct option is D $7.17m/s$

Maximum height reached by Kangaroo $H=2.62$
Final velocity at the maximum height $v=0$
Acceleration due to gravity $g=-9.8m/s^2$ (minus sign for downward direction)
Using $v^2-u^2=2gH$
$\therefore$ $0-u^2=2(-9.8)\left(2.62\right)$
$⟹u=\sqrt{2\left(9.8\right)\left(2.62\right)}=7.17m/s$