Boy Scouts are firing model rockets in a field. One boy used a radar gun to determine his rocket had a lift-off velocity of 34 m/s. How high did the rocket travel?

1 Answer
Apr 4, 2018

Assuming that the rocket had a vertical lift-off velocity the applicable kinematic expression is

#v^2-u^2=2gh#
where #v# is final velocity, #u# is initial velocity, #g=9.81\ ms^-2# acceleration due to gravity and #h# is height of rocket

At maximum height the velocity of rocket will be zero. Noting that #g# acts against direction of initial motion, inserting various values we get

#(0)^2-(34)^2=2(-9.81)h_max#
#=>h_max=(34)^2/(2xx9.81)#
#=>h_max=58.92\ m#