Answer: 20.4m
Explanation:
Mass = 0.145kg
Initial velocity, Vi =20m/s
Initial kinetic energy K =1/2mv^2
Initial potential energy Ui = mgx = 0joules
: From conservation of energy,
Uf + Kf = Ui + Ki ( where f represent (final) )
Thus
mgXf + 0 = 0+1/2 mv^2
Xf = Vi^2/ 2g
= (20m/s) ^2/ 2(9.81m/s)^2
=20.4m