Question

a body projected vertically up reaches a maximum height of 9.8m it's time of flight is

Answer 1

first use 3rd equation of motion to calculate the initial velocity

$v^{2} -u^{2} =2gh$

v=0

g=-9.8

h=9.8

⇒$u^{2} = 9.8^{2}$

so u=9.8m/s

Now use 1st equation of motion

$v=u+gt$

⇒t= u/g= 1 second (ans)

Answer 2

Answer:

first use 3rd equation of motion to calculate the initial velocity

v=0

g=-9.8

h=9.8

⇒

so u=9.8m/s

Now use 1st equation of motion

⇒t= u/g= 1 second (ans