A stone is projected in the air vertical upward with an initial velocity of 5m/s

Find a) tr and tf
b) H, highest distance has reached
c) where is the stone has reached after t=5.0sec

2 answers

I have no idea what you mean by tr and tf

highest distance:
PotentialEnergyatTop=KE at bottom
mgh=1/2 mv^2
H= 1/2 (5^2)/9.8 m

at t=5 seconds
h(5)=H(0)+vi*5- 1/2 9.8 *5^2
= 25-4.9*25...looks like it is well below ground...
Time of rise, time of fall :)